Middle of the Night is a psychological thriller novel by New York Times bestselling author Riley Sager, published by Dutton/Penguin in paperback on May 20, 2025. The paperback edition runs 400 pages.

The story follows Ethan, a man haunted by insomnia and the memory of a childhood trauma: at age ten, he fell asleep in a backyard tent with his best friend Billy in a quiet New Jersey cul-de-sac, and by morning Billy was gone—the tent sliced open, no trace of him ever found. Thirty years later, Ethan reluctantly returns to his childhood home, and strange things begin happening in the middle of the night, forcing him to confront the dark secrets buried beneath his picture-perfect suburban neighborhood.

An instant New York Times bestseller, the novel blends elements of gothic suspense, childhood trauma, and suburban mystery. It is suitable for fans of literary thrillers and horror-adjacent fiction.