After convicting a superior for corruption and shooting off a gangster's crown jewels, the career of Hamburg's most hard-bitten state prosecutor, Chastity Riley, has taken a nose dive: she has been transferred to the tedium of witness protection to prevent her making any more trouble. However, when she is assigned to the case of an anonymous man lying under police guard in hospital - almost every bone in his body broken, a finger cut off, and refusing to speak in anything other than riddles - Chastity's instinct for the big, exciting case kicks in.