Riley Sager and Tom Ryan on coincidentally writing thrillers with the same premise

Riley Sager’s tenth thriller, The Unknown, was released in August and immediately hit number one on the NYT bestseller list. Return to Breakneck Island, the first sequel to Tom Ryan’s USA Today bestselling The Treasure Hunters Club comes out on October 6th.

When they exchanged ARCs at Thrillerfest earlier this year, the two writers quickly realized that their respective novels share a very specific plot point and decided the coincidence was worth exploring.

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Tom Ryan: I’m always excited when details of the next Riley Sager novel are revealed, but I was really intrigued—not to mention a bit unnerved—when I read the back cover copy of The Unknown, because it was eerily similar to the premise of my own upcoming novel, Return to Breakneck Island. In your book, characters in the present day are drawn into the long unsolved mystery of five individuals who disappeared from a remote island in 1926.

In my book, characters in the present day are drawn into the long unsolved mystery of five individuals who disappeared from a remote island in 1932. As it turns out, the stories are completely different in every other way, but this central plot point was so eerily similar that I thought it would be fun to go back and forth a bit and discuss the inspirations behind these stories, and how they evolved.

To kick things off, I’m curious if the island was always part of this story. Did you have a specific place in mind when you began to write about New Avalon?

Riley Sager: Between my book, your book, and Widow’s Bay, remote islands seem to be having a moment. I think that’s because genre fare—be it mystery, thriller, horror or some combination of the three—hits differently when it’s on an island. Being surrounded by water instantly raises the stakes.

For The Unknown, I knew from the start that it needed the sense of isolation only an island can provide. It would have been a very different book if I’d set it on the mainland. Hence New Avalon, which is an oval of land in the middle of a vast lake.

It was inspired by a trip to Lake Champlain I took in 2024 to see that year’s solar eclipse. We witnessed the eclipse from a boat in the middle of the lake, very close to the Canadian border. Along the way, we passed several very small islands that contained only one or two structures. They struck me as a very good place to set a creepy book, especially with the mainland being visible yet also just out of reach.

What was the inspiration for your Breakneck Island?

TR: I live in Nova Scotia, which is almost entirely surrounded by water, and my husband and I have spent a lot of time exploring the coastline by sailboat in the summertime. About ten years ago, we dropped anchor near a small, uninhabited island and hiked to the lighthouse on its farthest point. Like most lighthouses these days, this one is now completely automated, but there were several abandoned buildings surrounding it that spoke to an earlier reality, when people—often families—were required to keep the lighthouses operating.

When I started considering possibilities for a sequel to The Treasure Hunters Club, I remembered that abandoned island community and began to imagine a family of lighthouse keepers who disappeared without a trace from their island home a hundred years ago. Who were they, and what happened to them? Could my contemporary protagonists solve the mystery a century later?

RS: Was it easy inserting established characters into a brand new mystery? I write standalones, so I’ve never had to do it. I imagine there’s a sense of familiarity, but also perhaps a bit of struggle trying to make them consistent with the previous book.

TR: I’d never written a sequel before, and I loved every minute of it. The series features three, very different, main characters—a struggling writer in her early thirties, a middle-aged gay man, and a teenage sleuth—and I genuinely wanted to know what had happened to them in the year since the events of the first book. That curiosity about my characters was the driving force behind the sequel and gave me a solid foundation to build on.

But within these familiar parameters, I had free reign to build a new mystery, which kept things fun and fresh. I’m curious about your characters: the modern timeline of The Unknown centres on a group of characters producing a film, and the historical timeline features a group of women with unusual gifts. How did you land on these characters?

RS: I wish I could remember who came first, the women who vanished from the island in 1926 or the actresses who are making a movie about it in the present day. I guess it was a little of both, starting with Daisy, whose diary from 1926 inspires the film-within-a-book, and Marin, the actress cast as Daisy in 2026.

It was a lot of work making these two groups of women their own individual characters while also serving as funhouse-mirror versions of each other. I wanted the reader to see the women from the past, then the actresses playing them in the present and think, “That’s really good casting.”

But it was also fun to take these pampered Hollywood people and plop them down on an allegedly haunted island.

TR: Have you ever been part of a film production?

RS: I haven’t. But you have, right?

TR: I worked in film and television production for several years, and I like to think I learned a few things about storytelling that followed me into my writing career. Coincidentally enough, more than twenty years ago I wrote and directed a stop-motion animated film about a family tending a lighthouse. There was no murder—it was for kids!—but there was a ghost.

Which brings me back to The Unknown. This isn’t the first of your novels to have a supernatural edge, but this one really leans all the way into the uncanny in a way that serves the story on multiple levels. You do such a great job of bringing gothic thrillers into the present day, so I have to ask: have you ever had a supernatural experience?

RS: I get asked this question a lot, and my answer—no, never—always disappoints people. Then again, I haven’t tried too much to change that. I don’t believe in ghosts, yet they scare me all the same, which means I must believe in the supernatural a little bit. Regardless, other than a few silly attempts in college—Ouija boards, touring an allegedly haunted house on Halloween, visiting a spooky graveyard at night—I’ve stayed away from such things. What about you? Have you ever witnessed something go bump in the night?

TR: Nova Scotia is thick with supernatural stories and legends, from ghost ships and haunted houses to spectral pirates guarding hidden gold, but I’m sad to say I haven’t spotted anything suspicious… yet. I hold out hope that someday I’ll have a brush with the beyond, but for now I’ll just have to lean on the old stories I grew up on to help inspire my novels. So what’s next for you, Riley?

RS: A very good question…that I can’t answer. My next book is being treated like a state secret. Only a handful of people know what it’s about. I’m excited, because it’s like nothing I’ve ever done before, and also nervous, for the very same reason. We’ll find out what readers think when it comes out next summer.

Can you share anything about what you’re working on? If so, does it involve a return to Maple Bay?

TR: I will absolutely return to Maple Bay sooner than later, but for now I’m working on something entirely different, a murder mystery with a speculative twist. It was slated to come out next fall, but it’s proven so complicated and challenging that I asked my publishers to give me some more time to work it out and so it will release in Spring of 2028 instead. I think it will be worth the wait, and the extra time means I’ll be able to read your next book and make sure there are no more wild coincidences!

This was a lot of fun, Riley, thanks for chatting. I’ll see you at Thrillerfest next year!

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