What if the one you call isn't the one who comes?

When Fortune accepts a housesitting job in brownstone Brooklyn, she becomes embroiled in the building's grisly history that ensnares the residents and lures back a serial killer with supernatural connections.

Patsy, the apartment's owner, is keeping secrets. The apartment also has its own secrets that not even Patsy suspects, revolving around the ex-priest who lived there after a failed exorcism. Both Patsy and the former Father Guenther Ives have invited forces that are not what they think. Soon, Fortune is forced to confront both Father Ives and a larger, nonhuman evil.