Roos Beckman has a spirit companion only she can see. Ruth—strange, corpse-like, and dead for centuries—is the only good thing in Roos’ life, which is filled with sordid backroom séances organized by her mother. That is, until wealthy young widow Agnes Knoop attends one of these séances and asks Roos to come live with her at the crumbling estate she inherited upon the death of her husband. The manor is unsettling, but the attraction between Roos and Agnes is palpable. So how does someone end up dead? Roos is caught red-handed, but she claims a spirit is the culprit. Doctor Montague, a psychologist tasked with finding out whether Roos can be considered mentally fit to stand trial, suspects she’s created an elaborate fantasy to protect her from what really happened. But Roos knows spirits are real; she's loved one of them. She'll have to prove her innocence and her sanity, or lose everything.