PC. Amy Harris finds a young Asian man dead in a police interview room, and realises that her fellow officers are framing her for murder.

Amy, newly recruited to the Ghost Squad, investigates a group of police officers who have been working under cover to expose a sex trafficking network.

Amy is sent under cover to work alongside a police sergeant and expose his corruption.

Amy investigates the background of a Chief Superintendent in line for further promotion, but spots her dining with her own boyfriend.

Amy has to discover which of three police officers working on a witness protection programme is corrupt, and make sure that the witness reaches court.

Amy goes under cover to investigate a detective inspector accused of involvement in drugs and prostitution.