Line of Duty Season 1 Episodes

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Season 1 Episode Guide

Episode 1 - Episode 1

When a counterterrorism raid goes tragically wrong, Detective Sergeant Steve Arnott refuses to participate in a cover-up. Ostracised by his colleagues, he transfers to an anticorruption unit, AC-12, led by Superintendent Ted Hastings.AC-12 is in the process of investigating one of the Force's most respected officers, Detective Chief Inspector Tony Gates. Not only has Gates just been awarded Officer of the Year, his squad has returned the best crime figures for three consecutive years. Hastings is convinced that no one can be that good. Uncomfortable in his new role, Arnott initially questions the whole investigation but Hastings is determined that his new recruit will uncover Gates' secret.However, Gates' secret is something altogether unexpected. Appearing to be a devoted family man, he is conducting a passionate affair with an old flame, Jackie Laverty. When Jackie implores him to help cover up a minor traffic offence, Gates reluctantly agrees.Gates' squad, TO-20, is nicknamed 'the big, sexy crime unit' - manned by Detective Sergeant Matt 'Dot' Cottan, Detective Constable Nigel Morton and Detective Constable Deepak Kapoor. Under pressure to have a more gender-balanced team, Gates agrees to give Detective Constable Kate Fleming a trial on TO-20. A talented detective, Kate soon wins Gates' approval - and then starts winning his trust.When Arnott delves into Gates' case files, Gates is confident of seeing off the investigation. But that's before he realises that Jackie's minor traffic offence may have been something altogether more serious.


Episode 2 - Episode 2

Having been duped into covering up Jackie's crime, Gates is desperate to conceal any evidence of his involvement. Jackie visits the police station to ensure she's in the clear, but Gates is determined to sever ties with her. Fleming's suspicions are aroused; working secretly with Arnott, they set about connecting Gates to Jackie. As the net closes on Gates, he's forced to choose between his marriage and his career - and finds himself plunged into an even more dangerous situation than he thought.


Episode 3 - Episode 3

Gates comes round in Jackie's house. Her blood stains the carpet, but there's no sign of her body. As Arnott races to the house, Gates must act fast. Arnott is convinced Gates played a part in Jackie's disappearance. With Fleming's help, the anticorruption team tries to trap Gates into revealing his involvement in covering up Jackie's crimes. Desperate to get his man, Arnott oversteps the boundaries, risking the entire anticorruption operation - and his own career. Meanwhile Gates wrestles with the nagging doubt that Jackie may still be alive.


Episode 4 - Episode 4

With Arnott off the case, Fleming is determined to save the anticorruption operation single-handed. Desperate for proof of Gates' involvement in Jackie's crimes, Fleming pushes her relationship with him to the limit. She must test how far she'll go to gain his trust. However, her behaviour causes Morton to question if she harbours an ulterior motive. If Fleming makes the tiniest slip-up, Morton will blow her cover.