The Enigma Challenge

Chapter One

One

Madrid, Spain

I step out into the buttery warmth of the early-morning Spanish sun and wish for the millionth time that I had more than three full days in Madrid. There is so much I want to see, but this morning I have an urgent appointment with the devil.

The walk is easy but long, and I’m sweating a bit by the time I stand in front of the statue of the devil in question.

It sits in the middle of a fountain at the center of a roundabout in the cool green of the Retiro, Madrid’s huge city park.

The ángel Caído, or the fallen angel, is a bronze rendering from Milton’s Paradise Lost, and, according to my Madrid guidebook, the only known statue of the devil in Europe.

It also might be the site of the kickoff puzzle for the Enigma Challenge.

I walk around the statue so I have a good view of Satan’s verdigris face, mouth open in shock at being cast out of heaven.

The devil’s bronze hair streams upward as he falls, and the whole thing is a tad dramatic.

I get it, because I’ve also come from drama.

My ex-boyfriend, Eric, is fuming back at the hotel where I’ve just left him after ending our almost yearlong disaster of a relationship.

He’s also my boss, which is one of the many reasons I broke up with him.

It’s unfortunate that it took arriving in Spain to end things.

This is a work trip; we’re in Madrid for the International Conference on Cryptology, and I’m presenting a paper here for the first time.

Eric has meetings set up for us too. Although I’m looking forward to giving my lecture, I have to admit that most of my attention has been on the puzzle competition, called the Enigma Challenge, held at the conference.

It’s a series of puzzles with an unspecific cash reward—millions, it’s rumored.

It doesn’t matter what the prize is. It could be an “I win!” sticker for all I care, because God, I love a puzzle.

Information about the Enigma Challenge is elusive.

I heard about it years ago as a graduate student, but anyone I talked to about it said, I’ve never played it, so I don’t know how it works.

Internet searches reveal frustratingly little.

Here’s what I know: The game consists of five puzzles, and they change every year.

Supposedly there’s one puzzle that kicks off the game, a throwaway puzzle, at this conference.

The reason I’m standing here this morning in front of the ángel Caído statue is because of a Reddit thread I found titled how to find kickoff puzzle this year?

? in which people stated, without any proof, that the kickoff puzzle might be found at the Temple of Debod, a reassembled Egyptian temple in Madrid, or maybe at the entrance of the Metropolitano Stadium, where Atlético Madrid play.

But deep in a subthread buried under a speculative discussion of the Madrid Codex, a Mayan book on display at the Museo de América, an anonymous commenter posted The kickoff puzzle this year in Madrid is with the fallen angel.

At the time, I had another tab on my laptop open with Top 10 things to do in Madrid, and the ángel Caído statue was on it.

There was something about this comment that seemed more trustworthy than the others.

It might have been the lack of jokes or speculation, or maybe it was the quiet-seeming Yes, I’m sure reply the commenter gave someone questioning them.

Whatever it was, I’m here now. At worst, I get to see an interesting statue.

It might be fate, even if avoiding Eric after our breakup was a factor in coming here this morning.

“Don’t enter the Enigma Challenge under any circumstances,” he told me on the flight yesterday from San Francisco. “It’s dangerous and people get hurt.”

“How badly do they get hurt?” I asked.

“It’s not a joke, Zoe,” he said in that commanding tone I loathe. “It’s too difficult to solve.”

But “too difficult to solve” is an invitation, not a threat. And anyway, the Enigma Challenge has been solved in previous years, so it obviously can be done.

As my boss on my postdoc grant studying ciphers in literature at Chessmont, a small private university in the Bay Area, Eric is the English-department head and has some authority.

But it certainly doesn’t extend to the lure of puzzle crack—which is exactly what the Enigma Challenge is to me.

I get it from my dad, who relished any kind of puzzle, but especially ciphers.

He was part of online amateur codebreaking groups, and for years, up until his death, people sent him ciphers to break.

When I was small, he let me help him with whatever he was working on.

Figuring out The New York Times crossword together was our Sunday-morning ritual.

If he hadn’t died when I was sixteen, I have no doubt he’d want to play the Enigma Challenge too.

“Always finish the puzzles you start, Zoe,” he would say. “Otherwise life gets messy.”

Now, at age thirty, I have a deep love for all things code and cipher related. I never stood a chance at resisting the Enigma Challenge.

Eric had plenty of other instructions about this conference too. “Don’t forget we have that meeting with my Spanish cryptology contacts on the first day. I’d hate to see you miss the opportunity to talk to working cryptologists. And it goes without saying, stay away from Dane Seaver.”

I’ve never met Dane Seaver, but Eric hates him intensely.

His crimes, apparently, include cheating his way onto peer review committees, stealing research, and having the absolute nerve to lack a PhD.

As far as I can tell, Dane Seaver is a well-respected expert in cybersecurity, a go-to for an opinion on articles about threat prevention and network security, and the author of multiple papers on cryptology.

It’s not a huge leap to see that Eric is envious of Dane.

I asked Eric whether he would like an “I Hate Dane Seaver” dartboard for his birthday, but he didn’t find that funny.

But none of that matters now. I am here, in this majestic city, standing in front of the devil statue.

Rid of Eric—romantically, anyway, with my paper to present in a few hours, and I’m pursuing my own investigation of the Enigma Challenge.

I circle around the fountain again, looking for any sign of a code or a clue.

It’s so exciting. It’s exactly how I wanted to spend my first morning in Spain.

On the fountain, gargoyles spit streams of water out of their mouths while clutching lizards and grimacing.

I imagine all kinds of weird people are drawn to the statue.

It is, my guidebook gleefully notes, mounted a diabolically intentional 666 meters above sea level.

But there’s nothing I can see that resembles a clue, and I’m starting to worry that the Reddit commenter was as clueless as the rest of them.

I’m about to turn away when a flash of light reflecting off metal catches my eye.

Relief floods me, cool as the fountain water, because there, tucked between a short boxwood hedge and the cement wall of the fountain, is a metal sign. On it is a series of numbers.

08 01 14 03 06 19. 07 15 15 13. 20 15. 04 21 03 09 01. 25 15 21.

The numbers sear into my head the way codes and ciphers do when I see them, although this sequence would mean nothing to the average person.

A shivery spike of excitement zips through me.

This is definitely the Enigma Challenge.

Already I’m trying to get a sense of the occurrence of numbers, given that frequency analysis is my first tool when starting a puzzle.

The number 15 seems to appear the most, so that’ll be a vowel.

Movement shifts in my periphery, and I realize someone has come to stand next to me.

I turn to see a tall man gazing at the face of the fallen angel.

The man is dressed in black slacks and a black button-down, like gloomy office attire, his hands in his pockets.

He is in his thirties, probably, a few years older than me.

He’s handsome in profile, lean, with a muscled chest and arms. His black hair is short, and the side of his face has a gorgeous contour.

A pigeon boldly lands on the devil’s bronze thigh, which makes the perfect flat perch. The pigeon lets loose a stream of white from its rear.

“Well,” the man says as the guano drips down the fallen angel’s knee. “That’s one way to comment on the subject matter.”

His voice is deep and silky, and I clock him as American.

He turns to face me fully. He’s as beautiful as his profile suggested. His eyes are a deep, dark blue.

“You’re here for the cryptology conference,” he says. “Right?”

“Yes.” The word is out of my mouth before I can stop it. “How did you know?”

“You’re staring at the numbers on that sign, for one.” He turns back to the statue. If he’s realized the numbers are a code, then he’s probably here for the Enigma Challenge too. Although he could be a competitor, it’s thrilling that I could be standing here next to a fellow puzzle solver.

“I could be staring at them because they seem out of place at a statue of the devil,” I counter.

“That’s true. You’re not writing them down.”

I shrug. “No need. Photographic memory.”

The American turns to look at me again, but before he can say anything, our attention is diverted toward heavy footsteps sounding across the asphalt. A man is running full tilt toward us.

Before I can react, the man slams into the American.

They topple to the cobblestones around the statue, and I jump back, trying to catch up with what I’m seeing.

I can feel my heart start to race, and my mouth falls open as the guy who appeared out of nowhere is now on top of the American, and he’s holding a knife—a knife?

I’m so horrified that for a flash I wonder if I’m on a YouTuber’s prank show or if this is Madrid media’s brand of humor.

But it seems entirely real, and the two are thrashing around, which I don’t understand at all because the American doesn’t look like someone I’d trifle with.

There should be no contest. His biceps are easily twice as big as his attacker’s, and—why am I looking at his arms?

“Hey!” I yell, which is as ineffectual as it is silly. I scrabble in my bag for my phone to call emergency services—what are they here in Madrid? Is it 999? My phone isn’t in my backpack—shit! Where is it? My heart is slamming in my chest. I must have left it at the hotel.

The attacker is still on top, aiming the knife at the side of the American’s neck.

The American holds him back, and I can see them both straining, muscles pushing, as they try to overcome each other.

It’s horrible, and I’m worried the American won’t prevail.

What if I’m about to witness a murder? Before I can think it through, I take a step forward and stomp on the attacker’s wrist. His hand spasms open, and the knife spills out.

The American takes advantage of this and pushes the guy off him.

I quickly aim a kick at the knife, and it flies across the asphalt of the roundabout, skittering around like a propeller.

The American and his attacker continue to thrash, and then, just as quickly as he appeared, the attacker gets up and staggers back before running in the opposite direction and into the trees toward the rose garden.

I don’t know what to say. I’m breathing heavily even though I wasn’t the one engaging in a slasher Greco-Roman fight.

“That wasn’t a good idea,” the American says reproachfully as he gets up and dusts himself off. “Kicking his knife away.”

My eyes widen. “Jesus. You’re welcome.” The whole thing feels surreal.

“You had no idea what the situation was.” He runs his hands through his short hair like I’m the one who pissed him off.

“The situation looked like you were getting your ass handed to you.” My words are a little shaky.

His eyes widen in disbelief, and he gives what I think is supposed to be a glare, but I’m pretty sure there’s also smothered amusement in it. Before I can ask questions, he turns and breaks into a run after the guy, who has already disappeared into the rose garden.

I glance up at the fallen angel’s open mouth of shock. Same, Satan, same.

I’m alone again in front of the statue. It’s as though nothing happened, yet my heart is still racing and I feel completely unnerved.

Something did happen. I turn to begin the ten-minute walk back to the hotel.

The lane through the Retiro is tree lined and peaceful, which helps regulate my heartbeat and work the adrenaline through my body.

Then I’m back out on Paseo del Prado, walking past busy cafés with charming wrought iron streetlamps and balconies, under a cornflower-blue sky framed between buildings with baroque flourishes.

It’s like that skirmish was a fever dream.

I’m passing the front desk at the hotel when the receptionist waves at me.

“Dr. Wilder,” she calls. “I have something for you, left by Dr. Howland.”

I veer over to the counter, and she hands me a small bundle contained by an oversize rubber band. It’s my phone wrapped in a sheet of hotel stationery with Eric’s messy handwriting on it.

You forgot your phone after our discussion this morning. Try to remember to keep it with you since Madrid is a new city. Don’t forget we have that meeting with my contacts here at eleven thirty today. I’ll collect you after your presentation.

I grimace. Collect. He manages to be a condescending ass even on paper.

He’s been harping about this meeting with his contacts for a week, but as far as I can tell, they’re people he’s never met whom he wants to impress.

At least now I know where my phone was. I give an extra grimace for being thoughtless enough to forget my phone in his room, but in my defense, I was in a hurry to leave after telling Eric we were done this morning.

I thank the receptionist and step back outside into the sunshine. It figures he’d leave for the conference without me. It’s not that I want to walk over with him, but leaving ahead of me is a classic Eric power flex. I’m so glad we broke up.

I’m halfway to the conference center, lulled by the heat of the spring sunshine, when unease slithers down my back.

I left my phone in my hotel room, not his.