Today's Edition · Sunday, September 20, 2026

Book of the Day

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Today's Book of the Day is The Unknown by Riley SagerSeptember 20, 2026.

Today's Book of the Day

The Unknown by Riley Sager book cover for the Book of the Day thriller book review

The Unknown

Riley Sager

Riley Sager's The Unknown drops a film crew on the Vermont island where five women vanished in 1926, then dares the cast, and the reader, to decide if the new disappearances are sabotage or something the island never let go of. It's a gothic thriller that trusts its central image enough to make you sit with it before the killing starts again.

From the review

Five dresses hang from the oak tree at the center of New Avalon, one for each of the five women who vanished from the island in 1926, and they're the only trace the women left. New Avalon sits on sprawling Lake Faraday in Vermont, and a century ago it was a commune for spiritual mediums. A century later, Riley Sager sends a film crew there to shoot a movie about that same unsolved case, and puts struggling actress Marin Keane in the middle of it. The setup for The Unknown does what Sager's strongest books do: it takes an unsolved crime, builds a fresh one directly on top of it, and dares you to keep the two apart. It's a gothic thriller with a horror engine, the historical case and the present-day one trading suspects almost from the first night on the island. The research trip is Sager's excuse to drop present-day characters straight into a hundred-year-old mystery. Marin's chapters run alongside pages from the diary of Daisy Rue, one of the vanished mediums, and the two timelines needle each other more than they simply alternate. Daisy's account of a séance gone wrong reads like local legend right up until the present-day cast starts hearing strange noises at night and finding symbols the island's old residents left behind. Sager holds the choice between folklore and coincidence open for a long stretch, and that patience gives the early chapters their held breath.

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Today's Book of the Day is The Unknown by Riley Sager. Our full review covers the verdict, who it's for, and what to expect before you commit.
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