(door squeaks) (suspenseful music) (footsteps clicking) (pensive piano music) - (Geoffrey) Everyone loves a good mystery and Chicago has enough of them to fill a library.

(blows air) I'm Geoffrey Baer.

Let's see if we can solve some of Chicago's most perplexing mysteries, like these.

(curious music) - A saucer shaped-gray disc hovering above Gate C17.

- Where did this thing come from?

- Whoa.

- Whoa.

- It's supposedly a portal to hell.

- This?

- Right here.

(curious music) - Caution.

Do not dig.

(bell ringing) (Geoffrey scoffs) We don't know if there's anybody in there.

- We don't know if there's anybody in there.

- Why is that garage in the front?

- Anybody here that wants to communicate?

- Perhaps not.

- Like, wow.

It's an alligator.

- It disappears and is never seen again.

- Follow me down the rabbit hole... (curious music) ...as we explore Chicago Mysteries.

(curious music) (door squeaks) (footsteps clicking) (curious adventurous music) (gentle music) (airplane engine whirs) Thousands of aircraft of every size and description fly in and out of O'Hare International Airport every year.

But one overcast day in late 2006, airport workers and even some pilots spotted something in the sky they had never seen before and couldn't make sense of.

- [Dave] O'Hare Tower, this is Dave.

- [Sue] Hey Dave, it's Sue from United Tower.

- [Dave] Hey, Sue.

- [Sue] Hey, did you see a flying disc out by C17?

(suspenseful music) - [Geoffrey] Was a UFO really hovering over the United Airlines terminal?

- I have corroborated this with over a dozen people.

These are aviation professionals, and they all describe the exact same phenomenon.

- [Geoffrey] Chicago Tribune transportation reporter, Jon Hilkevitch, broke the story on New Year's Day 2007.

- And they all said it was a saucer-shaped gray disc hovering maybe 1400 feet above gate C17 in the United Terminal.

What they described is just this immense energy, this alleged object just broke through the clouds.

- Shot straight up?

- Shot straight up, and created this donut of blue sky in the air.

- Made a hole in the cloud?

- Made a hole in the clouds.

- [Geoffrey] Most of the witnesses who spoke to Hilkevitch were airline employees.

- Ranging from ramp walkers, the people that bring the planes in and out to the gate, baggage personnel, mechanics.

The copilot on C17, he actually opened his windscreen.

He climbed up and looked at this object.

- He stuck his head out the window.

- Yeah.

- And saw it?

- Yeah.

- [Geoffrey] Hilkevitch says United Airlines and the Federal Aviation Administration told him there were no reports of any UFO activity at O'Hare that day, and they said nothing showed up on radar.

But Hilkevitch filed a Freedom of Information Act request that revealed a far different narrative.

- [Sue] Dude, there was a disc out there flying around.

- There was a what?

- A disc.

- [Dwight] A disc.

Like a Frisbee?

- [Sue] Like a UFO type thing?

- Yeah.

Okay.

- Okay.

(laughs) - [Dwight] Yeah.

- I FOIA'd the air traffic tapes.

So you have the banter between the control tower and various people on the airfield who said they saw it.

- [Person 1] Oh, we saw it a half hour ago.

- [Person 2] Who saw it?

- [Person 1] A whole bunch of us over at the Charlie Concourse.

- [Person 2] Really?

You guys did?

Who is this?

- [Person 1] A United taxi mechanic.

- When we learned that both the FAA and the United Airlines were lying to us, were covering up this story.

- Yeah.

- That's when editors, and you know, and I got a lot more interested.

- Why would they not want to tell you the true story?

(pensive music) According to Hilkevitch, neither the government nor United Airlines launched an investigation.

He says the FAA also floated another theory, a freak weather phenomenon called a hole-punch cloud.

A what?

- East Winds at six.

44 at O'Hare.

- [Geoffrey] Well, who better to explain this to us than legendary WGN chief meteorologist, Tom Skilling, whom we caught up with shortly before he retired.

I should get a shot of you.

I should get a shot.

- This is where the magic takes place.

- [Geoffrey] Hole-punch clouds might be rare, but viewers sent Tom plenty of photos of them over the years.

- If you came across that scene, you would say, "Wow."

- Somebody's invading?

- Yeah, exactly.

- What is a hole-punch cloud?

- Well, the cloud is composed of super cooled water droplets.

So what happens is you get a plane to fly through and the agitation turns them into little ice crystals.

- Like instantly?

- Instantly.

These ice crystals, gravity goes to work on them and pulls them down and opens up a hole in the clouds.

- Okay, if it's a hole-punch cloud, something had to have made the hole in the cloud, right?

- Oh, absolutely.

Will we ever have an absolutely precise explanation of it?

Perhaps not.

(suspenseful music) - [Geoffrey] You can't really solve any of our mysteries?

(laughing) - [Tom] Ah, yeah.

I'm of no use to you, Geoffrey, I apologize.

I failed ya.

(ominous music) - [Person 3] Some of our pilots on the ground were reporting a UFO sighting at a thousand feet from the seaside of the airport.

Did you guys do anything about that?

- [Person 4] You know what?

The ramp tower called me, I wanna say about 10, 15 minutes ago.

(dramatic music) - If there was something actually there, you know, you'd think the FAA would be concerned about it.

- Right?

- And would investigate.

(curious music) - [Geoffrey] Was this the biggest story of your career?

- No, the biggest story of my career was my Pulitzer Prize.

- Oh, there you go.

(laughing) - My fear, however, is that when I die, my obit will be this damn UFO story.

(airplane engine whirring) (eerie music) (eerie music continues) - Yeah, to the right, that's Philo Carpenter, the apothecary... - [Geoffrey] Author Adam Selzer has made a career out of digging up mysteries in cemeteries.

In fact, his tour business is called "Mysterious Chicago," but he didn't always have the nerve to wander through the graveyard gates.

- When I was a kid, I was terrified of cemeteries like, but once I'd been in a couple of them, it stopped being scary to me and they just started getting interesting.

I realized just how many mysteries there are to solve, just walking around in these places.

- [Geoffrey] We asked Adam for a mini mystery tour of Chicago's dearly departed and mysteriously, he didn't start in a cemetery.

Adam, why is there a mausoleum in Lincoln Park?

- [Adam] Back in the days before the Great Chicago Fire, this was the city cemetery for a while.

- So we didn't have a lakefront park?

We had a lakefront cemetery?

- Cemetery, yeah.

(gentle music) - [Geoffrey] This tomb was built in 1858 for Tremont Hotel Magnate, Ira Couch, and members of his family.

- It was built to hold about a dozen people.

We know Ira himself was there.

Most reports say his parents and a few of their children who died in infancy.

- [Geoffrey] But even as this tomb was being built, people were having serious second thoughts about a cemetery on the lakefront where the high water table required shallow graves.

- They started worrying eventually that dead bodies would get mixed into the drinking water.

People who went there said that it was repulsive.

They stopped burials here in the 1860s, and the idea was to move everybody.

- [Geoffrey] So why is Couch's tomb still here?

- Some people say that the family objected.

Other people say it was just a matter of money.

So they decided to leave this one here for whatever reason.

- So we don't know if there's anybody in there.

- We don't know if there's anybody in there.

And now I kind of feel like if they did open that door, the whole thing might come tumbling down.

But then we'd know who was in there!

- [Geoffrey] We might never know if anyone is in this tomb, but we know for sure that when the city was relocating other bodies, they, well, missed a few.

(ominous music) And you're saying there are other people under our feet right now?

- Yeah, there might very well be some more skeletons and bone fragments out here someplace.

(dramatic stinger) - For more mysteries, Adam took us to a cemetery that's still a cemetery, Graceland in Uptown, where you'll find a Who's Who of Chicago's movers and shakers, like railroad car manufacturer, George Pullman, whose grave has been the subject of a persistent mystery.

(curious music) Alright, so the story is that George Pullman is buried under steel and concrete, so his body wouldn't be desecrated.

- Right?

- Is that true?

- Well, after he died, there had been a lot of high profile grave robberies lately, people being held for ransom.

So right after Pullman was buried, all the newspapers in town had big articles describing this massive grave full of concrete and steel to keep anybody from stealing it.

Whether it's true or not, we don't really know.

- Then there's real estate millionaire, Walter Newberry, whose bequest created the Newberry Library.

There is a legend about how he was preserved?

- Right, he died at sea and... - Oh.

(wind blowing) - Whoa!

- Whoa!

Look at that, there's ghosts in the cemetery.

He doesn't want this story told.

- In those days when you died at sea, they usually buried you at sea.

- Yeah.

- But the story went years later that they had preserved his body in a barrel of rum so that they could bury him properly.

- Wait, what?

- And that's how the story went.

All available evidence is that he was buried in a proper coffin.

But there's a terrific illustration that went out at the time with all these guys in top hats and curly mustaches rolling in the barrel undercover of darkness.

- So there might be a barrel of rum under here with Walter Newberry in it?

(eerie music) But not everyone at Graceland lived a famous life.

The sad story of this little girl, named Inez, was shrouded in myth until Adam's exhaustive research separated fact from fiction.

- There's an urban legend that she died when her mother locked her outside during a lightning storm.

- Oh!

- And now the legend goes that whenever there's a storm here at Graceland, the statue will vanish and her ghost will run around the cemetery.

(rain pattering) (fantasy music) - Now, it is raining and Inez is still here.

I have to say.

- So far.

- So far.

We'll let you know if she starts to vanish.

(thunder booms) After scouring census records and old letters, Adam learned that Inez's teenage mother had been abandoned by her drunken first husband.

And the lightning myth was just that.

- [Adam] We should really let her poor mother off the hook for that one.

- [Geoffrey] Yeah.

- [Adam] We know from her death certificate that Inez died of diptheria.

It wasn't a lightning storm.

- Do we know how old she was when she died?

- She was about 7 when she died.

- But she lives on here.

- But she lives on here.

- [Geoffrey] Just a little bit of redemption.

Thanks to an admittedly compulsive investigator who continues to bring more stories of the dead back to life.

(curious music) - A lot of these people, the last time anybody wrote about them was when they carved the epitaph.

And I feel like we're doing a good thing by finding out who these people were and telling their stories again.

(fantasy music) (jazz music) - One day each year, this sculpture on the University of Chicago campus supposedly sends a secret message.

It was unveiled during the Cold War with the Soviet Union.

And some believe that if the sun is shining on mayday, the International Celebration of the Worker, the sculpture casts a shadow of a hammer and sickle... (people singing in foreign language) The symbol of America's communist rivals.

(pensive music) To get to the bottom of this mystery, we went straight to the artist.

What is the name of this piece?

- Dialogo.

- Dialogo.

- Dialogo.

- Which means the dialogue?

- Dialogue.

Yes.

- [Geoffrey] Virginio Ferrari completed Dialogo in 1971, and he's been questioned about its mayday urban myth ever since.

- So there is this myth that this represents a communist hammer and sickle, casts a shadow on May 1st.

What do you think of that?

- That is a stupid thing.

(Geoffrey laughs) - Is it true?

- One hundred percent, no.

- Okay, we got it from the artist directly.

But is the artist telling the truth or is he secretly sympathizing with university radicals?

Well, let's consider Virginio Ferrari's backstory.

He arrived at the University of Chicago from Verona, Italy in 1966 during the Cold War with the Soviet Union.

- I was very happy to be here and I would do something to be against this country?

It doesn't make sense.

- [Geoffrey] Ferrari says he did design the sculpture with intent, but that it has nothing to do with communism.

So this is sort of universal.

- Universal dialogue.

- Dialogue.

- Okay.

- I was thinking about two figures.

They are meeting in the center of a square.

This one represents a wave of water that keeps together all the continents.

The other one is a big halo.

- A halo?

- Yeah.

To protect the dialogue.

- That's beautiful.

- Yes!

- And if any doubt remains about the hammer and sickle myth, Ferrari offers one final piece of evidence.

- So this one was there.

- Yeah.

- That one was here.

- He originally planned to orient the sculpture to face in an entirely different direction.

So it wasn't even intended to be- - No, no, no.

- Oriented to the sun.

- To pass the shadow.

- No.

- It was supposed to be the other way around.

- Yes.

They was afraid that piece was too big to stand there.

- The architect changed it just for the sidewalk?

- They asked me to move it, you know?

- [Geoffrey] So it really is nonsense?

- It's stupidity.

(Geoffrey chuckles) - Now in his 80s and all myths aside, Virginio Ferrari is happy with how Dialogo has held up.

Sometimes you see people climbing on it and sliding on it.

- Yes.

- How do you feel about that?

- That is really what I love.

- It is?

- Art should be for everybody.

(bright reflective music) (air whooshing) (reflective piano music) - [Geoffrey] John Corbett is a Chicago gallery owner.

I see why you need to keep it in a vault.

But one of his prized possessions isn't a work of art.

It's a very mysterious artifact that he found by pure chance after he drove past a junk store that was going out of business.

- I did a little U-turn and went into this store and this guy asked what I was interested in and I said, "I'm very interested in noir."

And at that point he said, "How about the mob?"

- [Geoffrey] The store owner handed Corbett this tattered envelope that stopped him in his tracks.

Inside was a typed manuscript from the 1930s containing an A to Z encyclopedia of Chicago's mobsters.

(swanky music) - "David "Yiddles" Miller, most notorious of all Chicago's pickpockets, has been arrested more than 2000 times in his 58 years.

His belly has an aldermanic swing, but his fingers are as nimble as ever."

- Oh, man, that is just, - Come on.

- I mean, that's just so good.

- That's publisher, Julia Klein, who partnered with John on releasing the manuscript.

She shares his love of its detailed character sketches.

- [Julie] The Aiello brothers.

"There were Dominick, Joseph, Carl, Andrew, and Theodore."

- [Geoffrey] And colorful language.

- [Julie] "Their name once was used by mothers to frighten their babies."

I love that one.

- Do you ever picture the person typing this, what the room looks like?

(typewriter clacking) - I imagine that it has that feel of a detective office, it's evening and it's raining, and you hear the clack of the typewriter.

Death Kiss Mary has proved a hoodoo to seven gangsters, all of whom are resting under green sod after having tasted the doubtful pleasures of the little lady's lips.

(typewriter clacking) (swanky music) - [Geoffrey] In the margins of the typed pages are handwritten notes and scrawled annotations.

- "The Death Kiss."

- And then what's in pencil?

- And it says, "The Kiss of Death," and somebody's correcting it so that it's "The Kiss of Death," not "The Death Kiss."

- And most mysteriously of all, the name of the author doesn't appear anywhere.

Do we know who wrote this?

- We do not know who wrote this.

- The mystery, yeah.

- The person who wrote it would be putting themselves in danger by publishing this if they were known, right?

- I mean, people are not eager to be outing anything about the mob.

(swanky music) We speculate that it was either an insider, it might have been a former mob member.

It could have been a former policeman.

- The cops told them to line up facing the wall.

- [Geoffrey] Nearly 10 years after its discovery, Julia and John published the manuscript under the title, "Bullets for Dead Hoods."

- [Julie] This is where the title comes from, it says- - [Geoffrey] So where was this?

- This was tucked into the envelope, "Collection bullets for dead hoods."

- [Geoffrey] Now all of us can read this anonymous author's take on little known Chicago wise guys.

- Little Jack is one of the dirty, lousy Gusick brothers.

- [Geoffrey] And A-list gangsters like Al Capone.

- Al had his alibi all fixed.

He was fishing off his Florida estate.

- [Geoffrey] John and Julia released the book in a facsimile format to preserve not only the colorful language, but also the time-worn look and feel of the original pages.

- Part of me wonders whether this isn't somebody who was a newspaper reporter.

- Oh, yeah.

- [Geoffrey] The hash marks, that's what a journalist puts at the end of their article.

- Is that right?

- Yes.

Look!

- Yeah.

- It's a journalist.

It's not a mobster.

(Julie laughs) I solved the mystery!

- Here's probably the only copy of this, abandoned in a junk store.

And then you have this thing that comes back to life.

- [Geoffrey] If you hadn't made that U-turn in your car.

- Yeah.

- It would be gone.

(swanky music) (pensive music) Next, a Chicago mystery that hits close to home for me.

I grew up just a few houses away from here in north suburban Deerfield, and right here in this little woodland was this crazy tree!

And back then there wasn't a fence around it and there wasn't a plaque.

So you had to wonder what kind of superhero could have bent this huge tree into an S shape?

The answer is, Native Americans bent it and tied it down as a sapling almost 200 years ago.

It's the indigenous equivalent of a road sign.

It's one of many trail marker trees once found throughout the region.

These trees guided native travelers through woodlands, some of which are forest preserves today, like Forest Glen, where we met with indigenous educator, Starla Thompson.

- Our history is kept within the oral tradition and it's alive.

- [Geoffrey] Starla helps to keep native traditions alive like this jingle dress dance.

She traces her own roots to the Otter Clan of the Forest Potawatomi and Santa Ynez Chumash Nations.

- This area had many nations, right?

And they knew how to navigate the landscape efficiently.

We're here along the Chicago River and we're not far from many trails.

Anyone at that time coming into this indigenous world had to walk upon our trails.

- Most of the trail trees have been lost to urban development or just old age.

But what about the trails they marked?

Are they lost, too?

That's the answer to another Chicago mystery.

If you've wondered why there are diagonal streets slicing through Chicago's famous right angle grid, it's because they were here first.

So there are many streets today that follow the trails, the paths of Native American roads?

- Mm-hmm.

Elston, Milwaukee, Clark, I mean those were all old Indian trails.

And I think it's kind of funny because the way the city has found to be most productive or efficient is to orient themselves along these trails.

- The diagonal streets.

- Absolutely.

- [Geoffrey] You know, it was always a center of transportation.

- Yeah, Chicago has always been an important place.

Indigenous people knew that.

The trails that we traveled upon got us through the state to the Mississippi.

It was all part of why Chicago is great and always has been.

(pensive music) (air whooshing) (swanky piano music) - [Geoffrey] Now let's hitch a ride with urban historian, Shermann "Dilla" Thomas, to explore a South Side neighborhood mystery.

Dilla is known for his popular history videos on social media.

- I just called dibs.

Lemme tell you it's history.

- [Geoffrey] But he's not just virtual anymore.

- I run Chicago Mahogany Tours where we take people on enriching and engaging neighborhood tours.

And I make it my business to show them why everything dope about America comes from Chicago.

(Geoffrey laughs) (swanky music) - [Geoffrey] Dilla took us to a puzzling patch of peculiar homes in the Chatham neighborhood.

Why are these houses so tiny?

And set so far back from the street?

With the biggest front lawns in Chicago, right?

- Oh, my goodness.

- [Geoffrey] These are the Garlows.

(swanky piano music) What does garlow mean?

- Well, it's two words pushed together, right?

It's garage and bungalow.

- [Geoffrey] They were meant to be temporary in response to a housing shortage following World War I.

It was a fast and cheap real estate solution to sell full-sized city lots with only a small brick house built along the alley at the rear of the property.

- It's set up in the back of the lot with the intentions of, you would later build on the front of the lot, a complete bungalow or a two-flat, and you would turn that garlow into a garage.

So there's a steel beam inside of the garlows and it's designed for you to remove the bricks and install a garage door.

(reflective blues music) When they were built, right after that, we run into the Great Depression.

- [Geoffrey] Yeah.

- And so that, even if your intentions were to build on that front lot and turn that garlow into a house, the Great Depression kind of stopped a lot of development here in Chicago and across the country.

- [Geoffrey] Some garlow owners did build on their big front lawns, but in a different way than intended.

You're supposed to build a house on the front of the lot, but somebody built a garage and kept the garlow as a house, right?

- Particularly on King Drive, one of the first things people ask me is like, "Wait a minute, why is that garage in the front as opposed to in the back?"

My guess is that it's a lot cheaper to build a garage in the front lawn than it is to construct a house.

Probably less permitting, too.

But a lot of Chicagoans like their garlows.

The garlows are such a unique thing to Chicago.

(swanky music) (air whooshing) (curious music) - Howdy!

- Hello.

- [Geoffrey] Some mysteries fall into a category we might call, "What the heck is that?"

- You don't need to be scared anymore.

At one point, maybe.

- Wait, anymore?

- Not anymore.

- But at one point, I should have been scared?

- Just trust me.

- Local oddities are a particular specialty of Jessica Mlinaric, author of the books "Secret Chicago" and "Chicago Scavenger."

So we asked her to show us a few of her favorites.

"Caution - do not dig.

There is no danger to visitors."

(Jessica laughs) Jessica started out by taking me to Red Gate Woods in the forest preserves of Cook County near Southwest suburban, Willow Springs.

"The world's first nuclear reactor buried here."

Why?

- The world's first nuclear reaction took place at the University of Chicago in 1942.

- Yeah, miles from here.

Not here.

- Miles from here, but in a very crowded urban area.

- Okay.

- So.

They didn't wanna continue those experiments with all those people around.

So they moved everything here to a top secret nuclear research facility in the woods.

- [Geoffrey] It was part of the Manhattan Project.

After World War II, the facility moved outta the forest and became Argonne National Laboratory.

- This facility here was decommissioned in the 1950s.

- [Geoffrey] Ah ha.

- And what did they do with all the nuclear stuff that they had sitting around?

Took it out in the woods and buried it.

- Right here?

- Right here.

- So would you throw down a blanket and have a picnic around you?

- I think it's a great spot for a blanket.

There's, you know, beautiful wild flowers and trees and a great breeze blowing.

So you can have a picnic on the nuclear reactor here.

(air whooshing) How about I give you a riddle?

- [Geoffrey] Next, Jessica took me to a remote stretch of Chicago lakefront on the far southeast side.

- We're here!

- So we have arrived.

Amidst the rail lines, power lines, and remnants of an old electrical generating station stands an ancient obelisk?

- This is Chicago's oldest monument.

- This?

- Right here!

- Frontier surveyors placed it here in 1838 to mark the boundary between the relatively new states of Illinois and Indiana.

It took us a little time to find it.

- It's remote today.

It was even more remote in the 1830s.

Sometimes the shifting sand from Lake Michigan would even cover up the marker entirely.

- Oh.

Oh!

That's the state line right there?

- I believe it is.

- Come here.

Let's go walk.

Let's do this.

- Let's check it this.

- So I'm in Illinois.

Indiana.

Illinois.

Indiana.

And it has stood the test of time?

- It sure has.

It's an amazing part of the region's history.

And I think more people should know about it.

(curious music) - [Geoffrey] After showing me a monument almost no one has ever seen, Jessica took me to an oddity that puzzles thousands of passers by every day, the leaning tower of Niles, Illinois.

- How did the Italian icon get to the north suburbs, you wonder?

- [Geoffrey] Jessica told me this half-size replica of the famous tower in Pisa, Italy, was erected in the 1930s by a Chicago factory owner named Robert Ilg.

It disguised a water tower that supplied a swimming pool in a park that Ilg built here as a rural retreat for his workers.

- And he also wanted to pay tribute to the power of science to better mankind.

So he was a fan of Galileo.

And so there's a plaque here dedicated to Galileo, as well.

- After Ilg's death, it became part of the YMCA beloved by generations of locals.

Okay, higher and higher.

The tower is not open to the public, but we got special permission to scale it.

The view gets better and better.

- It sure does, and I'm getting dizzier and dizzier.

- And hidden at the top, we discovered something truly amazing.

(bell chimes) To top off his tower, Ilg acquired 18th century bells from Europe.

I just rang a bell that was being rung in the 1700s in a church in Italy.

For some final insights, we got an audience with Niles Mayor and restaurant owner, George Alpogianis.

So how hard is it to engineer something that leans?

- I have no idea.

I make pancakes for a living, so I can't tell you that.

(Geoffrey laughs) - [Geoffrey] And like any good politician, he made sure to get the last word.

- Folks, come on by.

See the leaning tower.

It's a great place just to chill for a few minutes.

It's amazing and beautiful.

(Italian music) (ragtime piano music) - [Geoffrey] On a cold November day in 1915, a maritime mystery was pulled from the bottom of the Chicago River.

A diver named William "Frenchy" Deneau, said he stubbed his toe on this 40-foot steel vessel while he was laying cable along the riverbed.

- He's discovered an ancient submarine.

- Ah.

- And he calls it the Fool Killer.

- [Geoffrey] But is the Fool Killer really a submarine?

- [Mark] Where did this thing come from?

Whose was it?

- For Mark Chrisler, creator and host of the podcast, "The Constant," the mystery of the Fool Killer has been an obsession.

How long did you spend researching the Fool Killer?

- At this point?

I think it's been a...

The better part of a decade now.

- [Geoffrey] Frenchy Deneau got permission from authorities to salvage the Fool Killer.

And when it was raised, he claimed he found human bones and a dog skull inside.

- Who does the skull and the bones of the dog belong to?

- [Geoffrey] So there's a lot of mysteries surrounding this vessel.

- Yes!

- [Geoffrey] To profit from his discovery, Frenchy put the Fool Killer on display in a skee-ball arcade in downtown Chicago.

- But there was a big splashy ad to come and see the Fool Killer, the ancient submarine at the skee-ball arcade.

You can go in for 10 cents if you dare!

- [Geoffrey] If you dare!

Frenchy was already a minor Chicago celebrity for his role as a rescue diver after the steamship Eastland capsized in the Chicago River earlier that year, killing more than 800 people.

- He called himself Captain Frenchy Deneau, after that incident.

And he called himself the Hero of the Eastland.

What he said later was that he had recovered more than half of the victims, which is logistically infeasible.

(gentle music) - [Geoffrey] Frenchy seemed to love seeing his name in the papers.

So we went looking for clues to the Fool Killer story in the Chicago Tribune's vast archive with the newspaper's super sleuths, Marianne Mather and Kori Rumore.

- Come on in.

- So you call this a morgue?

- Yes, a morgue is synonymous with the archives in the newspaper world.

- In newspaper talk.

- Yeah?

- [Geoffrey] The morgue contains a treasure trove of Tribune history.

- So you never know what you're gonna find in the files.

- No kidding.

- It's always a mystery.

- [Geoffrey] And sure enough, Frenchy appears prominently in glass plate negatives.

- This is what we've got from Frenchy.

That's Frenchy Deneau, deep water diver.

- [Geoffrey] Okay, so we found Frenchy, but what about the Fool Killer?

Turns out that introduced another character into the mystery.

- Frenchy believes this submarine once belonged to a guy named Peter Nissen.

- Who's Peter Nissen?

- Well, that's our next mystery.

(suspenseful music) Peter Nissen, he's described in the Tribune as a bookkeeper from Denmark, but he had a little bit of a daredevil streak to him, and he came up with two different vessels and took them down the Niagara River Rapids and survived!

(suspenseful music) - [Geoffrey] Perhaps to tempt fate, Nissen named his vessels "Fool Killer 1," and "Fool Killer 2."

But it's Nissen's widely publicized and ill-fated "Fool Killer No.

3" that Frenchy apparently thought he'd fished out of the Chicago River.

- So here we have, if you can see this, the photos of the Fool Killer number three.

- [Geoffrey] It looks like a giant watermelon.

- Yeah, exactly!

- I said a potato, but she says watermelon.

- [Geoffrey] Yeah, I know.

It doesn't look anything like Frenchy's submarine.

We'll get to that.

The fatal voyage of Fool Killer number three took place on November 29th, 1904, when Peter Nissen, who also called himself, "Captain Bowser," set sail on a journey from Chicago to Michigan.

- The idea is it would roll and roll and roll and it was all wind-powered.

Now the wind was right, but everything else was probably wrong.

We know he made it 65 miles across Lake Michigan, but we don't know when he died.

- A fool and his killer are soon parted.

(ragtime piano music) Peter Nissen's death was widely reported in 1904, but maybe Frenchy just missed that story and a decade later only remembered the name "FoolKiller" - So the assumption apparently by Frenchy and by a lot of the papers, is that this thing, this submarine must have been the third Fool Killer.

And therefore, the insinuation is that the body belongs to Nissen.

- [Geoffrey] Mark Chrisler knew Frenchy got it wrong, but it took a tip to finally solve the mystery of the Fool Killer.

Turns out it wasn't a submarine at all.

- A listener of mine wrote me.

- To a podcast.

- To my podcast.

Wrote in to say that basically, "Hey look, I think I've got the Fool Killer."

- Okay and it's right here!

(swanky music) The listener sent Mark a photo of a life-saving power boat docked in the Chicago River and documented in a 1906 issue of Power Boat News.

- I knew that it had to be the real deal.

Within a few hours, I located the patents online.

- Did you just like, "Oh my God."

- Yeah, I was in a tizzy.

I was- (both laughing) Sort of tingling all over the place.

(swanky music) - One remaining mystery may never be solved.

What happened to the Fool Killer?

After the skee-ball arcade, it appeared in a circus in Iowa and then briefly at Chicago's Riverview amusement park.

But then what happens to it after that?

- It disappears.

By the end of that season at Riverview, it just goes away again.

It completely blips off the radar and is never seen again.

(swanky music) (audience cheering) (baseball cracks) (audience cheering) (baseball entertainment music) (baseball cracks) (audience cheering) - Baseball and hot dogs are synonymous so we've come out here to the ballpark to probe the most perplexing Chicago mystery of them all.

Why don't we ever, ever, put ketchup on a Chicago hot dog?

Axios reporter and food expert, Monica Eng says, it's because of all the other ingredients on our iconic Chicago hot dog.

- There are seven important ingredients and they really tell the story of 20th century immigration to Chicago.

So you take the bun, that's eastern European poppy seed bun.

- [Geoffrey] Okay?

- [Monica] Then the wiener, so Austria or Germany.

These were sold largely by Jewish Americans, sometimes kosher, some is kosher style.

Then you get the mustard.

That's very German.

- Not bright yellow mustard.

- Right, this became a very Americanized sort of milder version.

- Okay.

- [Monica] The piccalilli represents British culture, especially sweet piccalilli.

- [Geoffrey] Then, Monica says, the dog gets dragged through the garden thanks to Greek and Italian green grocers.

- Then you've got the onions.

Then you get the tomatoes.

Then you have your pickle spear.

Then second to last, you have the sport pepper.

There are two schools of thought on these.

One, that they came with Mexican Americans during the Columbian Exposition.

- Okay.

- Another theory is that they came during the Great Migration with African Americans who came from Louisiana.

- Louisiana, yeah.

- And Mississippi.

Final is the swoosh of celery salt.

(audience cheering) Woohoo, people like celery salt.

(Geoffrey laughs) Chicago was the center of celery production at the turn of the century, and celery was this health miracle!

So if you couldn't put a celery stick on it, at least you can put a little bit of our celery salt, which really deepens flavors.

- Wow.

Alright, Monica, why don't we put ketchup on a hot dog?

- Because Geoffrey, if you did, do you see this beautiful orchestra, all playing instruments together?

- It is.

- In harmony?

- Yes.

- The ketchup would smash it.

- Boom.

- Come in with a big bassoon and ruin everything.

- [Geoffrey] And what exactly makes ketchup the evil ingredient?

Well, it's loaded with sugar, which is why we liked it as kids.

For those who haven't outgrown this Frankfurter faux pas, the White Sox have provided a super-sized dispenser.

But there's a catch.

If you douse your dog, the Sox have installed a bell of shame, a tradition started at nearby 35th Street Red Hots.

(audience faintly cheering) - It tastes like I'm 5 years old.

- It's very sweet.

Alright, I will just, I'll do this to myself.

(bell chiming) (audience cheering) - So ashamed.

- I own my shame.

Whether at a neighborhood hot dog stand or the ballpark.

(audience cheering) Oh, single!

- Nice.

- Go, Sox!

Chicagoans wear their love for our signature style hot dogs on their sleeves.

Oh!

And sometimes on their laps.

- We need napkins.

- All right, go!

(suspenseful music) If that last story made you hungry for a hot dog, we'll fix that right now.

For this next mystery, we were granted exclusive access to the basement of a North Side condo building.

- It is pretty creepy down here.

(Geoffrey laughs) - [Geoffrey] In the 1890s, this was a sausage factory where Adolf Luetgert allegedly disposed of his wife's body after murdering her.

- Somewhere here in the basement, there were these three wooden vats, which are very important to the story of Louisa Luetgert and her disappearance.

- Author and historian, Robert Loerzel, has been studying the Luetgert case for 30 years and wrote an authoritative book about it called "Alchemy of Bones."

- There are parts of this basement that were here in 1897 when the murder happened.

- [Geoffrey] Adolf Luetgert was a German immigrant who was once so successful, he was called "Chicago's Sausage King."

But by 1897, he'd fallen on hard times.

His factory was closed.

And his wife, Louisa, was not happy about it.

- [Robert] They were having arguments.

Luetgert was also allegedly having some affairs at the time.

- [Geoffrey] They lived in a three-story mansion next to the sausage plant with their two young sons.

But Adolf often spent his nights in the factory.

- After Adolf Luetgert spent the night of May 1st, 1897, in the basement here working around this vat, the next morning his wife was gone and Luetgert doesn't seem too concerned about it.

And then he tells his workmen, "Oh, you gotta clean up the basement."

And they come in here and they see all this slimy goo.

And when the police went through it, they found some little pieces of what looked like bone.

(suspenseful music) - [Geoffrey] When authorities emptied the vat, they uncovered more than just bones.

(liquid draining) - They also found among all this slime that was in the vat, two golden rings, one of which had the initials LL engraved on it.

So this is when the police charged Adolf Luetgert with killing his wife and dissolving her body in the vat full of potash in the basement.

- [Geoffrey] Oh, my God.

Rumors quickly spread that Luetgert had turned his wife into encased meat and sold her to the public.

(suspenseful music) - There are reports about how people in Chicago became more reluctant to eat sausage for a little while.

- [Geoffrey] Luetgert was tried for murder in the late summer of 1897 in a courtroom packed with morbid gawkers and frenzied reporters.

(ragtime piano music) - It was sort of, you know, like the OJ Simpson trial where there's a media circus.

- [Geoffrey] After an eight week trial that featured the first ever use of forensic evidence, Luetgert's fate was handed to the jury.

The Chicago Journal, desperate for a scoop, snuck a team of reporters into the courthouse attic.

- They tied one reporter to a chair.

(Geoffrey laughs) Lowered him by a rope down the heating shaft of the courthouse so that he was right outside the vents of the room where the jury was deliberating.

(Geoffrey laughs) And he was eavesdropping on their deliberations and relaying it to the newsroom.

And while the jury was still out, the Chicago Journal started reporting verbatim reports of what the jurors were saying.

(gentle music) - [Geoffrey] In the end, the jury was hopelessly deadlocked.

But Adolf was convicted in a second trial and spent the rest of his life in Joliet State Prison.

(somber piano music) - There were stories, and I'm a little skeptical about this, that when he was there at the prison in Joliet, that he was being haunted by his wife's ghost.

(ghosts whispering indistinctly) - Louisa's ghost was also reported here in the factory basement by an unnerved police investigator.

He described a glowing orb of light and a white-clad figure said to resemble Louisa.

Oh wait, what's that?

(equipment clanking) Holy smokes.

- Um.

(equipment clanking) - I gotta say, those sounds are a little disconcerting in here.

(curious suspenseful music) Could Louisa's ghost be sending us a message?

Like, Robert, I'm skeptical.

You lead us.

But to explore the idea, we contacted self-described ghost researcher, Dale Kaczmarek.

Dale has been investigating reports of apparitions since the mid-1970s.

- [Dale] We have a lot of different detection equipment.

- [Geoffrey] He showed up at the former sausage factory with an arsenal of gadgets.

- So this actually has a temperature probe right here.

We could encounter what's called a cold spot.

- [Geoffrey] He says they could help us track down evidence of Louisa's spirit.

- That is the actual detection device.

An EM Vortex, sometimes called EM Pumps, were kind of feeding the ghost.

- [Geoffrey] Look at that thing.

- We've actually had some of these devices go off on command.

(device whirring) (suspenseful music) - Once we were fully equipped...

Okay, let's do it.

We canvassed the premises.

- It just said, "Here."

Anybody here that wants to communicate?

- To help us navigate the basement, we used vintage floor plans that had been printed in the newspapers during the trial.

Where do you think the vats were?

- Well, probably just this direction somewhere.

- And while our sensors did blurt out some intriguing messages, I got nothing here.

- Homicide.

Elemental.

- Homicide.

Elemental?

We still couldn't find any definitive answers about what really happened to Louisa Luetgert.

- [Dave] This is pretty much a dead end right here.

- Okay, I don't like you using the word dead.

(air whooshing) (somber reflective music) - This building?

- This building.

Yeah.

I mean this was her... - [Geoffrey] The search for Louisa Luetgert's ghost turned up empty.

So Dale Kaczmarek took us to a Chicago landmark, he says is crawling with ghosts.

- Sure, there's been reports of shadowy monk-like figures that have been seen upstairs.

(eerie music) - [Geoffrey] In this mansion, social reformer, Jane Addams, founded America's first settlement house in 1889 to serve a neighborhood that had become crowded with poor immigrants.

But is Hull House haunted?

- We're standing in an area that supposedly where there's a portal, an interdimensional doorway.

- Right there, right?

- Right behind us there.

- This folder is your Hull House research?

- Yes, this is something that dates back to the 1970s.

- The 70s?

Can I take a look?

- Sure.

(ominous music) Fascinating, Dale, I... Dale?

Hmm, looks like we'll need some help finishing that story.

Fortunately, Hull House Museum education manager, Nadia Maragha, knows all about it.

- We have a sort of a concrete slab out in the courtyard and it used to be the site of a fountain.

(ominous music) - And that's significant in some way?

- Yeah, it's supposedly a portal to hell.

(ominous music) So people have said that they've seen little girls dancing kind of or playing around that space and so they're known as the fountain girls.

(cacophony of ominous whispers) - So we know of Hull House for Jane Addams and all the social justice work.

We don't usually think of it as a haunted house.

- (laughing) If you listen to the stories, it's a very haunted house.

- In recent years, the Hull House Museum has embraced its supernatural side with the public.

- So this is Jane Addams' bedroom.

- Mm-hmm.

- [Nadia] Sometimes people have said they feel like they're being watched in this space.

- The most renowned paranormal occupant is said to be in the attic, the devil baby of Hull House.

So I reluctantly followed Nadia there.

So what supposedly happened in here?

- So this was supposedly where the baby, the devil baby is haunting.

(Geoffrey exclaims) - In 1913, Jane Addams wrote that there were these stories circulating around the neighborhood, that there was a child that was born to a family that had cloven hooves, had a tail, had horns.

Think your most stereotypical devil image (laughs), that was this baby.

- [Geoffrey] So why would a local woman have given birth to a devil?

And why did neighbors believe it was at Hull House?

- Jane Addams wrote, she was fascinated by this phenomenon.

It lasted, she said, for about six weeks.

And sometimes they would have like lines going down the street of people trying to get in to see the devil baby.

(somber music) - [Geoffrey] The tale varied depending on the teller's religion and ethnicity.

- [Nadia] According to the Catholic version, there was a very devout Catholic woman who married an atheist man.

He takes this religious image off the wall, throws it across the room and says that he'd rather have a devil in his house than that image.

And so lo and behold, (child crying) this devil child is born.

My favorite part is that Jane Addams said some versions of the story, the baby takes the cigar out of the dad's mouth and starts smoking it.

But then they don't know what to do with this baby.

So they bring it to Hull House.

Hull House takes it to the church and tries to get the baby baptized, but it like runs away from them and they have to catch it again.

And so they just lock it away in the attic of the house.

(suspenseful music) - [Geoffrey] Jane Addams came to see the story as a kind of folk tale that empowered immigrant women who had long been burdened with all the responsibilities of home and family and blamed for their failings.

- And it was sort of validating their experiences in a lot of ways.

- Because it wasn't their fault, it was their husband's fault?

- Exactly.

(laughing) - Do you think it's a haunted house?

- I...

I don't disbelieve it, so.

- Really?

- Yeah.

I have, you know, heard little things here and there or it never made real trouble for us, I'll say that much.

(suspenseful music) (Geoffrey gasps) (wolf howling) (dramatic pensive music) - [Geoffrey] At the break of dawn, on July 9th, 2019, photographer Ren Horst was at the Humboldt Park Boathouse, taking pictures of a soon to be 15-year-old for her Latin American quinceanera celebration.

- And she was actually right in front of me and I was a little a step back and her mom was behind us.

- [Geoffrey] As the morning sun rose over the park, Horst and her clients suddenly noticed, well something lurking beneath them in the lagoon.

- I took a look, looked right over there and saw two eyes above and we're like, "What is that?"

So I took a picture real fast.

(camera clicks) I had no idea what I was capturing at the moment other than some eyes that were above the water.

- [Geoffrey] But when Ren took a closer look at the photographs.

(camera clicks) - We're like wow, "It's an alligator!"

- [Geoffrey] How in the world did an alligator get into Humboldt Park Lagoon?

How could it survive in such an urban environment?

And most importantly, how could it be safely removed?

Reporter Mina Bloom with the online news service Block Club Chicago was first on the scene.

- I was in no way ready for what was about to happen.

- [Geoffrey] She'd been covering the Humboldt Park Beat for nearly a decade and was a bit skeptical that this was a legit lead, until she saw the photographs.

- I was like, "This is a gator."

Like there's no question.

(upbeat music) - [Geoffrey] Bloom broke the story and soon gator mania was everywhere.

♪ Hey ♪ - [Mina] All of a sudden there were thousands of people just like around the perimeter of this lagoon.

(upbeat music) - [Geoffrey] As a multi-agency effort began to rescue the elusive crocodilian, Block Club launched an online poll to give it an official nickname.

- [Mina] Croc Obama was one of them.

Ruth Gator Ginsburg.

But then we ended up going with Chance the Snapper.

It's a nod to our hometown rapper, Chance The Rapper.

(upbeat music) - [Geoffrey] Chance the Snapper made headlines all the way to Time Magazine and Chance the Rapper himself even gave his reptilian alter ego a shout out on The Tonight Show with Jimmy Fallon.

- Yeah.

- Do you have any words for Chance if he's watching?

- Oh yeah, man.

Keep your head up.

(audience laughing) They got you locked down.

They can have your body but they can't have your mind.

(all laughing) - The search went on for a week.

Who's gonna be the one to capture it?

- [Geoffrey] Animal control experts have been striking out for days and less qualified locals had started getting into the act.

- There was one guy who put a rotisserie chicken on a string and like dangled it into the lagoon.

(Geoffrey laughs) I remember that.

So they ended up bringing a guy from Florida.

Frank Robb is his name, but we ended up calling him Alligator Robb.

(group clapping) - In the middle of the night on July 16th, less than a day after arriving on the scene, Robb snagged Chance the Snapper using a fishing pole.

The mystery is how did it get into Humboldt Park Lagoon?

Does anyone really know?

- No one totally knows for sure.

- [Geoffrey] Did he escape from a zoo?

Swim up the Mississippi?

Did someone flush him down the toilet?

- One of the biggest pieces of evidence is he actually had a bent snout.

- [Geoffrey] In other words, it's likely poor Chance was caged and had grown so big his nose was pressed against the side of the enclosure.

- The prevailing theory is that this gator was somebody's pet and they got tired of it and they dumped it in the lagoon.

(bright music) - Happily, Chance now lives with a cadre of crocodilian companions in a Florida refuge called the St. Augustine Alligator Farm.

Hey Robb, can you see me?

We reached out to Alligator Robb for an update.

Where is he?

- [Robb] This is him facing us right here and him walking out.

- Hi, Chance.

Greetings from Chicago.

We love you, buddy.

Here's Humboldt Park Lagoon.

Do you remember this spot?

And so how big was he when he was here?

- Whenever we caught him, he was four foot and like an inch.

I'd say he's grown probably two feet.

You don't move him around very easy anymore.

And he's a big lizard these days.

(country music) - And there's a final twist to the story.

You became like a celebrity in Chicago.

You got to start Buckingham Fountain and throw out a pitch at Wrigley Field.

(audience cheering) How did it change your life?

- I had some heart issues, you know, not too long after all that.

(country music) - [Geoffrey] Not only did Alligator Robb save Chance's life, but Chance saved Alligator Robb.

- The media up there helped me find my doctor who did my heart surgery, helped fundraise the money to pay that off.

The city of Chicago is a lot of the reason that I'm still here.

(country music) - It became a story, not just about an alligator in the lagoon, but about so many people of different backgrounds, of different ages coming together.

It felt like the best of Chicago.

(country music fades) (suspenseful music) (suspenseful music continues) (suspenseful music continues) (suspenseful music continues) (suspenseful music continues)