Detective Inspector Cassidy 'Cass' is doing an early morning workout at home when a phone call summons him to attend a murder at a nearby hotel.He is due to retire in a few weeks, but he is inwardly pleased he has one last bite of the proverbial cherry. The killer has left a clue that has all police personnel baffled. This is only the first of what becomes a catalogue of serial murders. Each one similar with similar clues left. As he and his detective sergeant interview suspects, it begins to occur to Cass that someone close to him may be involved. Sometime into the investigation, Cass suddenly makes the connection, and what follows puts him in dire jeopardy. Was the person he reluctantly suspected involved? Or has fear of this possibility clouded his judgement? And who is the little girl put in danger by her mother's actions?