Under the Surface is a thrilling survival story about a girl and three friends who get lost in the Paris catacombs for days, while aboveground the boy she loves races to find her and a media frenzy begins. And the biggest question I get about it is: How did you come up with the idea?

So let’s dive into it!

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I’ve always loved survival stories

Survival stories aren’t anything new, and I’ve gobbled up as many as I can find over the years, starting in middle school with Hatchet by Gary Paulsen. It’s about a boy who survives a single-engine plane crash and finds himself alone in the middle of the woods, and it made me wonder what I would do if I were in his shoes: curl up in a ball and wither away until a bear sniffed me out, or be as resourceful and brave to make it out alive? I liked to believe it was the latter, but it’d probably be something more like option C: running in circles screaming myself hoarse until I trip over some vines and crack my sk—



It’s the first book I can remember having to read for class that I immediately re-read on my own. Then in high school I came across Alive by Piers Paul Read, a real-life account of a Uruguayan rugby team that crash landed in the Andes in the 1970s, which I read way too many times considering all the cannibalism.

Yeah. Those poor people.

Over the years I’ve kept seeking out survival thrillers, whether contemporary fiction like Hatchet, stories inspired by true events like Alive and Apollo 13, sci-fi like The Martian by Andy Weir, dystopians like Bird Box by Josh Malerman or the video game/TV show The Last of Us.

There’s something so damn compelling about people enduring in the face of impossible odds, and I can’t get enough. And for a long time, I knew I wanted to write a survival story of my own. I just didn’t know what that would look like.

2015: The idea takes shape

I first visited the Paris catacombs with my husband in 2015. In case you’re not familiar with the catacombs, here’s a small excerpt from Under the Surface when our main character Ruby first meets Julien, an alluring Parisian boy who takes her and her friends deep underground.

We’ve been dying to see the catacombs—the intricate web of tunnels beneath the city where the skeletal remains of six million long-dead Parisians line miles and miles of passageways in artistic arrangements. It has to be one of the creepiest things you can see on the entire planet, which obviously means I have to see it. Mr. LeBrecque added it to our itinerary after I begged and pleaded, but we’d be visiting the small touristy section—the only bit open to the public. Most of the other entrances scattered throughout Paris have been sealed for ages, and the only accessible ones are secret from everyone except for—

“You’re a cataphile, aren’t you?” I ask Julien, breathless. Suddenly his outfit makes sense. 

Selena sputters a laugh. “Did you just call him a pedophile?” 

“A cataphile,” Olivia pipes up. “It’s what they call the explorers who meet up in the catacombs.” Of course she’d know about them, too. “Illegally, I might add. Isn’t it dangerous down there?” 

“How’s it dangerous?” Selena asks. 

“It’s not if you know what you’re doing,” says Julien, “and where you’re going. And I do.” 

Unlike Ruby, who caves to her temptation to visit the restricted sections with Julien as her cataphile guide, I only visited the small touristy section open to the public, where you can’t get lost because there’s only one route you can possibly follow. Still, I was nervous! To get down into the catacombs, you need to descend a spiral staircase of 131 steps. I get claustrophobic in spiral staircases — on separate occasions when climbing the domes of St. Peter’s Basilica in the Vatican City and St. Paul’s Cathedral in London, by the time I reached the peak, I was a sweaty, shaky, panicky mess, and getting back down was an absolute nightmare.

Thinking about descending those 131 steps made my stomach turn, but I was so eager to see those ancient tunnels filled with bones, I braced myself and took the plunge. The descent wasn’t as bad as I’d imagined — the key is not to think about it too hard, take one step at a time, and keep breathing — and during our tour, I learned about the restricted sections that comprise a labyrinth spanning underneath much of Paris. In addition to all the interesting historical factoids our guide shared—how the ossuaries started out as limestone quarries, how in the 1700s entire city streets collapsed into the old abandoned quarries, how the cemeteries of Paris literally overflowed into neighboring basements and led the city to relocate millions of bodies, etc etc—I learned how the French police play cat-and-mouse with cataphiles who unseal entrances into the restricted sections, and how cave-ins, flooding, and other obstacles have caused explorers to get lost.

I learned how throughout the centuries, scammers would pose as tour guides to lure their marks into the dark maze, then would rob and abandon them to find their way out alone.

Can you imagine? Getting lost. In the catacombs. In those ancient, crumbling, dank tunnels. Where there’s no cell signal, and where if your flashlight battery runs out, you’ll be left alone in complete and utter darkness.

There it was. The kernel of an idea.

2017-2018: Inspired by the news

The idea of people getting lost in the Paris catacombs for days floated around in my brain for years. I was a new writer at the time and didn’t feel ready to tackle something so weighty, so I wrote two other manuscripts, including All Your Twisted Secrets, which wound up being my debut.

But every so often, I researched a little more, watched more videos, noted down interesting facts. I learned more about cataphiles, the urban explorers who roam and graffiti and party in the tunnels, and about their rules and customs. I watched YouTubers share their experiences traversing the dark corridors.

I also mulled over what characters I could throw into this terrifying situation. Two things I knew early on:

  1. I wanted it to be a heart-wrenching romance where a girl and boy falling in love (Ruby and Sean) get torn apart on a trip abroad when she gets lost underground and he has no clue where she went.
  2. I wanted the girl to get lost with a best friend and former best friend with whom she’d had a falling out, and examine friendship betrayals, breakups, makeups, all while facing a life-threatening situation, an allegory for how day-to-day squabbles consume us while we ignore greater threats that can destroy us (e.g. climate change).

Then in June 2017, I saw a news story about teenagers who were rescued from the Paris catacombs after being lost for three days. Here’s CNN’s coverage.

News story about teens lost in the Paris catacombs on CNN

This story didn’t gain much traction, and if you try to research it, you won’t find much. I never attempted to reach out to the parties involved; their experience was, I’m sure, quite harrowing, and I hope they’ve made a full recovery in peace. But seeing this brief snippet was validating: the premise was realistic and not too far-fetched, as it quite literally just happened.

At the time, I was busy revising All Your Twisted Secrets, querying, signing with my new agent, revising it again, doing an R&R for my first publisher, and getting my first book deal, so another year passed.

Then in June 2018, a junior football team in Thailand got trapped in a flooded cave for 12 days. This time, the news coverage was swift and monumental, and it became a global phenomenon as the world watched the boys get rescued.

Seeing the media’s reaction on a global scale compelled me to finally email this pitch I’d been honing for years to my agent.

2019: Back to the catacombs for research

My agent loved the idea right away. But contractually, my publisher wasn’t obligated to consider my next proposal until All Your Twisted Secrets was delivered and accepted, and that was still a ways off. At this point, though, I was determined for this to be my next book, so in 2019 I headed back to Paris and down into the catacombs to do real research.

These pictures are from this 2019 trip:

Diana Urban's pictures of the Paris catacombs from 2019

I also explored the area surrounding the Luxembourg gardens and found a street corner I visualized as the spot where Ruby, Selena, and Olivia meet up with Val and Julien in chapter 4.

Street near Luxembourg gardens that was inspiration for the meeting point in Under the Surface

I took loads of pictures on this trip and was ready to turn it into a real book.

But the universe had other ideas.

This newsletter is about how I got the idea for Under the Surface, not about the messy innards of the publishing industry. But I want to explain why it took so long to get this book published. I’ll summarize the next sequence of events as succinctly as I can:

  • My first publisher wanted to wait until All Your Twisted Secrets launched to see how it performed before buying my next book, relinquishing their first right of refusal (aka my option clause).
  • My agent took the proposal for Under the Surface out on submission to other publishers. Meanwhile, I started working on a proposal for a new idea: These Deadly Games.
  • We got some rejections. One actual quote: “We think this should be pushed more as a thriller and less as a thriller/romance.” Editors didn’t want Sean’s secondary POV. I wasn’t willing to publish the book without it. Sean is half of the love story, and his chapters give readers a reprieve from the catacombs every so often while letting them see what’s going on aboveground in Paris.
  • The pandemic hit. Shelter in place began March 12, 2020.
  • All Your Twisted Secrets released March 17, 2020. Bookstores were closed. Amazon only shipped essential goods that week. My hardcover sales were massively impacted. Despite the pandemic preventing the book from breaking out in a big way, it still did well and went to a second printing within two weeks, and ebook sales were high for a YA book. I’m so grateful to my readers for this.
  • A month later, my first publisher officially declined to buy another book from me because “sales of All Your Twisted Secrets weren’t as high as we hoped.”
  • I gestured wildly at the world and laughed.
  • My agent took my new proposal for These Deadly Games out on submission. It sold two weeks later to Macmillan.
  • In 2021, Penguin Random House (PRH) signed me for Lying in the Deep.
  • n 2022, my editor at PRH bought Under the Surface and an untitled Book #5. I finally got to start drafting Under the Surface. At this phase I incorporated the idea of [redacted] chasing the group lost underground.
  • In 2023 I rewrote the book two more times during developmental edits.

Now we’re finally just a few months away from Under the Surface’s release on August 13, 2024. It’s been one hell of a journey, and I can’t wait to share this story with you! If you’d like to preorder, you can do so here:

Autographed & personalized copy | Amazon | Barnes & Noble | Bookshop

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