The Unknown: A Novel by Riley Sager 

The Unknown: A Novel by Riley Sager — the highly anticipated tenth thriller from the #1 New York Times bestselling master of suspense.

In 1926, five women vanished from a remote island in Vermont. The only trace left behind: five dresses hanging from the branches of an old oak tree.

A century later, struggling actress Marin Keane lands the role of a lifetime in a major motion picture about the unsolved mystery of New Avalon. The catch? She and the rest of the cast must spend a week on that very island for research — no phones, no internet, just the isolated location and its dark history.

New Avalon was once a commune for spiritual mediums… until they all disappeared. Some say the women simply left. Others believe they were murdered. The most unsettling theory, drawn from a diary left behind by one of the vanished, claims a séance gone wrong summoned something that took them one by one.

As the film crew settles in, strange noises echo through the night. Mysterious symbols appear. And then the disappearances begin again.

With fear and suspicion rising, Marin turns to the old diary, desperate to uncover what really happened a hundred years ago — and stop the island’s terrible history from repeating itself.

Atmospheric, twisty, and impossible to put down, The Unknown delivers everything Riley Sager fans love: dual timelines, escalating dread, and a final revelation that will leave you reeling.