The Unknown by Riley Sager
“Once again, Riley Sager has combined the thriller genre with the supernatural in a way that no one else has so successfully since Stephen King.”
I was already a huge fan of Riley Sager before The Unknown. I’ve read all of his previous best-selling thrillers and even got the opportunity to interview him once. So I was pretty sure right from the start this would be a good book. I just didn’t know it was going to be this good.
The Unknown is a wonderfully creepy, spooky and mesmerizing story about five women who mysteriously disappeared in 1926 from a remote island in Vermont amid speculation that supernatural forces were responsible — and about a movie company that comes to the island now a century later to try to recreate these events on a film set.
The legend over the years, based in part on a diary left behind by one of the missing from 1926 — a young woman named Daisy Rue — is that a séance gone wrong somehow unleashed some force of evil that took all of those women one by one.
The only thing ever found on the island once they were gone was five dresses hanging from the branches of a tree there, each belonging to one of the missing women.
A Century-Old Mystery Returns
Sager dramatically grabs the reader by the throat right from the first chapter, which ends with the actress playing the lead role in the movie getting a chilling text on the boat ride to the island warning her to stay away: “Don’t set foot on that island. If you do, I swear you WILL regret it.”
And sure enough, history on the island begins repeating itself as the modern-day women from the film soon experience the same things that happened there a century earlier — eerie seances that seem to communicate with the dead, the people on the island being cut off from communication with anyone else and — most terrifying of all — more women disappearing the same way they did 100 years earlier.
Is this really a frightening series of supernatural events happening all over again on this island?
Is it all just being staged to give some kind of sensational publicity to the movie being shot there?
Or is there something else entirely going on here — something so unbelievable that no one can even comprehend it?
The story is told by Daisy herself — well, actually by two Daisys. The Daisy who left behind the diary talking about all the strange events on the island before she disappeared like the others — and the actress playing the role of Daisy now, an unknown named Marin Keane who was strangely plucked from obscurity for the starring role.
Sager masterfully alternates chapters between the Daisy from 1926 and this present-day woman playing the role of her reading about it all in Daisy’s diary.
Marin — the movie Daisy — becomes more and more convinced that the answers for everything that is happening to them now are in the real Daisy’s diary, which begins with these haunting words from a century earlier:
The Darkness.
It’s presence can be felt all over this island.
And now it’s waiting for us. The only two people who remain. The Darkness has already claimed the others. I worry I will suffer the same fate,
Likely soon.
A Finale You’ll Never See Coming
After that, it’s one shocking twist after another as the pages of The Unknown just fly by.
Much of the story is a variation of a locked room mystery as in both cases — back in 1926 and again now in present day for the film crew — suspicious circumstances have taken away the boat that is their only way off the island and left them stranded with whatever evil forces are still lurking there.
Some of the most compelling parts of this book are Sager’s chilling descriptions of seances that the women hold to try to communicate with the dead — both in 1926 and then being recreated again by the film crew on the island.
Both 100 years ago and now in present day, the seances summon up an evil spirit by the name of Azra who communicates terrifying messages to them about being trapped in hell, tells them to “Let Me Out” and seems to be the dark force behind all of the horrifying things that have occurred.
No spoilers here, but the explosive ending — with the dramatic and shocking truth about what really happened on this island, both now and a century earlier — is one you’ll never see coming.
Once again, Riley Sager has combined the thriller genre with the supernatural in a way that no one else has so successfully since Stephen King.
Like all Sager’s books beginning with Final Girls, his debut thriller, The Unknown is one terrifically compelling read that will stay with you long after you’ve finished the final page.
Publish Date: August 4, 2026
Genre: Fiction, Thrillers
Author: Riley Sager
Page Count: 368 pages
Publisher: Dutton
ISBN: 979-8217044092