From amazon.com:
Hot on the heels of Richard Castle's #1 New York Times bestseller Heat Rises comes the fourth novel in the Nikki Heat series, Frozen Heat. Nikki Heat and Jameson Rook are together again, facing an unsolved murder mystery that has haunted Nikki for ten years. NYPD Homicide Detective Nikki Heat arrives at her latest crime scene to find an unidentified woman stabbed to death and stuffed inside a suitcase left on a Manhattan street. Nikki is in for a big shock when this new homicide connects to the unsolved murder of her own mother. 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 is forced to confront unexplored areas of her mother's background. Facing relentless danger as someone targets her for the next kill, Nikki's search will unearth painful family truths, expose a startling hidden life, and cause Nikki to reexamine her