The Unknown: A Novel

By Riley Sager

The first edition of this stunning hardcover features designed endpapers, a foil-stamped case, hued edges, and a shimmery jacket!

In 1926, five women disappeared from a remote island in Vermont. Now, one hundred years later, it’s happening again.


Struggling actress Marin Keane is shocked when she lands a role in a major motion picture about the unsolved mystery of New Avalon, an island on sprawling Lake Faraday in Vermont. She’s even more surprised when she learns that the role requires a weeklong research trip to that very spot.

Because New Avalon isn’t your ordinary island. A century ago, it was a commune for spiritual mediums—until they all vanished in 1926. The only trace of them was five dresses hanging from the branches of an old oak tree in the middle of the island, one for each missing woman. Some locals say they simply left. Others think they were murdered. But the prevailing opinion, thanks to a diary left behind by one of the vanished, a young woman named Daisy Rue, is that a séance gone wrong conjured something supernatural that took them all one by one.

Not long after arriving, Marin and her castmates, including legendary actress Violet Wright and white-hot director Ronan Peters, begin to realize all is not right with New Avalon. They hear strange noises in the night and notice mysterious symbols left behind by the island's previous occupants. And after a sudden health emergency leaves Marin, Ronan, and the other actors stranded on the island, the disappearances begin again.

Is it the work of someone trying to derail the movie? Or is the island’s alleged supernatural past catching up with the present? As fear and suspicion mount, Marin turns to Daisy’s diary, hoping it holds the key to figuring out what really happened to the women of New Avalon—and how to keep the island’s terrible history from repeating itself.

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Published Aug 4, 2026

368 pages

Average rating: 6.8

5 RATINGS

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Community Reviews

ValerieRuiz
May 11, 2026
4/10 stars
don't come after me for this one, ok? Ok great. I didn't like it, but I didn't hate it. I kinda sorta am happy I got approved for an ARC bc I would have probably been upset about spending my hard earned money on this book that I truly feel missed the mark. The premise sounds promising—spooky, creepy, locked room vibes. But somewhere along the way I just wasn't really into it. And the truth/plot twist was pretty "meh". This one felt different from Sager's other books which I normally LOVE. I feel like the 1926 storyline didn't work for me along with the letter excerpts. I actually DNFed initially bc I think I was just distracted with my personal world, and now that things have cleared up, I decided to give it a second try. TBH, I would have been fine leaving it as not finished. Anyways, I received an advanced copy of this book from NetGalley in exchange for a review.

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