NYPD Homicide Detective Nikki Heat gets more mystery than she imagined when she arrives at her latest crime scene. The body of an unidentified woman has been found stabbed to death and stuffed inside a suitcase left sitting on a Manhattan street. A startling enough death, but an even bigger shock comes when this new homicide surprisingly connects to the unsolved murder of Detective Heat's own mother. The gruesome killing of this Jane Doe launches Heat on a dangerous and emotional investigation, rekindling the cold case that has haunted her since she was nineteen. Paired once again with her romantic and investigative partner, top journalist Jameson Rook, Heat works to solve the mystery of the body in the suitcase while she also digs into unexplored areas of her mother's background—areas Nikki has been afraid to confront before, but now must. Facing relentless danger as someone targets her for the next kill, Heat's search will unearth painful family truths, expose a startling hidden life, and cause Nikki to reexamine her own past. Heat's passionate quest takes her and Rook from the back alleys of Manhattan to the avenues of Paris, trying to catch a ruthless killer. The question is, now that her mother's cold case has unexpectedly thawed, will Nikki Heat finally be able to solve the dark mystery that has been her demon for ten years?
The entertaining fourth Nikki Heat thriller, ostensibly written by the mystery novelist character of the ABC-TV drama Castle, showcases the feisty relationship between Nikki, an NYPD homicide detective, and Jameson Rook, a journalist who featured in 2011's Heat Rises. At a crime scene on Manhattan's Upper West Side, Nikki examines a woman's frozen body found in a suitcase inside a refrigerated delivery truck. To her shock, Nikki recognizes the suitcase, which was stolen from her mother the night her mother was murdered years earlier. Since her mother's killer was never found, Nikki naturally thinks the new death may be her best chance yet of determining the truth. Fortunately, if implausibly, her superiors allow her to handle the investigation. The new case forces Nikki to learn more about her mother's life, in particular why she abandoned a promising classical music career. Diverting banter ("Isn't domestic spying illegal?" asks Nikki; "It is if you're doing it right," replies a former CIA agent) helps compensate for a less than credible main storyline.