Young FBI agent Nicole Bonnet receives a mysterious package. Inside she finds a complicated mechanism that appears to be a message from a serial killer. This is just the beginning of an epic duel of minds between Nicole and the ruthless murderer, who leaves playing cards by the bodies of his victims as signature. Bonnet will have to use all her wits to solve the case and stop the killer before he strikes again. Does she have what it takes to understand the mind of a psychopath, as complicated as his puzzles?