Line of Duty

Steve Arnott discovers his target is the city's top detective, Tony Gates.

Having been duped into covering up Jackie's crime, Gates is desperate to sever ties with her; as Arnott and Fleming close in on his secret, Gates is plunged into a more dangerous situation.

Arnott is convinced Gates plays a part in Jackie's disappearance; with Fleming's help, the anti-corruption team tries to trap Gates into revealing his involvement in covering up Jackie's crimes.

Desperate for proof of Gates's corruption, Fleming pushes her relationship with him to the limit; her behavior causes Morton to question if she might not be such a loyal colleague after all.

With Gates on the run, the anti-corruption team comes under pressure to close the case; Arnott is forced to make some tough decisions about his loyalties; Fleming and Hastings go all out to catch Gates.