A USMC gunnery sergeant is murdered on his last day in the Corps. A sadistic serial killer is targeting the clients of Miami's fidelity testing agencies. Probationary police officer Kate Shannon is asked to infiltrate the Sirens' agency in a desperate attempt to discover how the killer is targeting his victims. But Kate has a motive of her own in accepting the honey trap assignment, unaware that the greatest threat she'll face will come from someone she trusts completely. An omission that she may well pay for with her life.