Gallagher's densely layered murder mystery is part police procedural and part psychological thriller—a combination that unfortunately slows the book's pacing to a grisly crawl. Maggie Quinn, a disgraced Chicago homicide detective, gets pulled back into the pursuit of a serial killer she was chasing before her young daughter died and her world fell apart. From her luxurious townhouse, courtesy of an appropriately slimy ex-husband, Quinn recuperates from a suicide attempt and visits her imprisoned father, who happens to be able to pull strings within the corrupt Chicago Police Department. Called in as a consultant to the homicide squad, Quinn battles her psychic demons—expressed as a physical manifestation of darkness—as she pursues a homicidal surgeon whose chilly and chilling character is the focus of some of the book's best writing. While Gallagher takes some genuine risks, such as killing off a particularly sympathetic character, she lards on subplots that are not fully explained and come too slowly to help move the plot forward. The courtroom theatrics at the end are implausible and the resolution is, like much of the writing, overwrought and unsatisfying.