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Book: “The Unknown” by Riley Sager
Publishing Info: Dutton, August 2026
Where Did I Get This Book: I received an eARC from NetGalley
Where You Can Get This Book: WorldCat.org | Amazon | Indiebound
Book Description: 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.
Review: Thank you to NetGalley for sending me an eARC of this novel!
Perhaps some people remember that last year I read and reviewed Riley Sager’s previous novel “With a Vengeance” and didn’t really care for it. I have generally been super down with Sager’s books but that one didn’t really work for me. I was excited to see that his next novel, “The Unknown”, was stepping away from locked room whodunnits and coming back to a spooky horror/thriller story. I’m already really excited for a story with people mysteriously disappearing on a strange island, but if you add in spiritualism and potential witchcraft it just sweetens the deal. And I’m happy to report that we’ve returned to form with “The Unknown” because I found it to be super fun!
Sager knows how to craft a fast paced thriller that keeps me engaged, and “The Unknown” kept me invested pretty much from the start. We jump between two timelines: the first is that in the present day, where aspiring actress Marin has been cast as the lead in a highly anticipated historical horror film, which is based on a true story of multiple women mysteriously disappearing on the island New Avalon in the 1920s, inspired by the diary of one of the women who wrote of potential ghosts, demons, and witchy activity. Marin and the rest of the cast have been brought to the island to experience it in a method way, and things start happening to THEM in a similar way as the diary. The second timeline is the diary of Daisy, who ended up on New Avalon and wrote the entries the movie takes inspiration from. It’s a great hook, and Sager creates a mystery with themes of grief, spiritualism during the 1920s, and misogyny across centuries. Marin was sometimes a grating narrator, but she is the perfect protagonist who has so much to lose if the movie doesn’t work out, but also becomes more and more frightened as the movie crew slowly disappears in the same way the other women did. I liked the way Sager showed the circumstances, revealed the twists, and turned up the tension with what could be ghostly encounters and witch activity.. Or maybe something more Earthly.
And the atmosphere is top notch. An isolated island with a strange and witchy history is always a fun locale to explore, and Sager really figures out how to bring the Gothic vibes to the tale of isolation and questions of supernatural hijinks vs insanity in this book. I really enjoyed some of the beats and imagery, with a few points making me genuinely creeped out, and the claustrophobic island with woods, a potential murderer, and potential ghosts was eerie. I also liked that we got the history of New Avalon through the diary entries that could line up with what Marin and the rest of the cast was experiencing so we could expand the lore of the island and get it in context. While it’s true that I could parse out some of the surprises, overall I liked how things ultimately unfolded and the setting made it that much more addictive.
I’m quite pleased that “The Unknown” was an enjoyable read! Sager may have stumbled last time around in my eyes, but clearly that was a temporary stumble!
Rating 8: A tense psychological horror/thriller novel that brings us back to the Riley Sager basics! A great summer read as we start to wind down the season.
Reader’s Advisory:
“The Unknown” is included in the Goodreads article “A Month-by-Month Guide to Summer’s Biggest Mysteries and Thrillers”.
The Library Ladies 