Review: The Unknown by Riley Sager

August 5, 2026

Synopsis:

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:

A group of actors spending a few days on an island to get into character for a movie that reflects events from many years ago sounded like a promising start to the story.

It becomes clear immediately that the mysterious events from the past, along with several women who went missing without anyone ever learning what happened to them, mean this will not be a story of sunshine and rainbows. Learning bit by bit about what really happened on the island highlighted that the events of the past could only result in something bad happening in the present, and I was immediately drawn into the mystery and eager to see how it would unfold. I wanted to understand what happened to these women, and I was not prepared for the truth.

The storytelling worked very well for me. Switching between the current timeline and discovering the events of the past through diary entries provided some answers while raising even more questions. The tension built slowly, and when everything finally exploded, I was not prepared for the full consequences. Were some aspects a bit over the top and predictable? Yes, but that did not take away from what was a very entertaining read that had me glued to the pages from beginning to end.

🌙 Recension: The Unknown by Riley Sager
📚 Genre: Fiction, Mystery, Thriller
📅 Release Date: August 4, 2026
📖 Publisher: ‎Dutton
📗 available in various formats
📱 Read as: Kindle
💸 I received a free copy and am voluntarily leaving a review.
📆 Pages: 364
⭐️ 4/5