Six years have passed since Aurelia last set foot on Usher Isle, a remote island off the coast of Maine that once felt like a second home. But when a letter arrives from her childhood friend, Madeline Usher—written in the grip of a mysterious illness—Aurelia cannot refuse the plea to return.

Upon her arrival, she is drawn once more into the rhythms of the isolated Usher household. But Madeline is not the girl she remembers, her condition worsening in ways no physician can explain. And Roderick—the man she left behind—has been changed by time and grief.

It is not long before something feels wrong. The air hangs heavy, the rooms oppressive, and sleep brings vivid, disquieting dreams. At night, she glimpses Madeline wandering the grounds in her nightdress, though by morning no one speaks of it.

As Aurelia searches for the cause of her friend’s decline, she becomes increasingly uncertain whether what she’s experiencing is illness, madness, or something more nefarious. And the longer she remains, the more it feels as though the house might not let her leave.