Line of Duty: Series 4

  • As the hit BBC police drama continues, DCI Roz Huntley (Thandie Newton, Westworld) is suspected of deliberately ignoring key evidence to close a career-defining case. Called in to investigate, AC-12's Superintendent Hastings places DS Kate Fleming undercover inside Roz's team, while DS Steve Arnott applies pressure from the outside. As suspicions mount, AC-12 comes under threat. SDH.

    Episode 1

    After months of hunting a serial killer, DCI Roz Huntley faces intense pressure to apprehend a suspect. Michael Farmer is caught and charged for the crimes, but doubts about the young man's guilt lead the chief forensic investigator to AC-12.

    Episode 2

    AC-12 continue their investigation into Operation Trapdoor, concerned that Michael Farmer will go to jail for crimes he didn't commit. But suddenly the investigation falters when their key informant goes missing.

    Episode 3

    AC-12 uncover holes in the case against Michael Farmer and expect that the real killer could still be at large. As they struggle to sort through the evidence, Steve challenges Roz's husband, Nick, to account for his wife's whereabouts on the night Tim Ifield went missing.

    Episode 4

    Still suspicious of Roz's husband, Nick, AC-12 interrogate him, but the discovery of new forensic anomalies puts the spotlight back on Roz. Their case against her seems solid until Roz starts dismantling their evidence with inside information of her own.

    Episode 5

    Roz struggles to assuage her husband's suspicions, and AC-12 find a new angle to pursue in their case against her. Nick's suspicions over his wife's guilt continue to grow and a cold case gives AC-12 another way to challenge Roz.

    Episode 6

    AC-12 question Nick, but they remain convinced of Roz's involvement. As they come closer to the truth surrounding Tim Ifield's murder, the team also hope to unmask Balaclava Man, but the ramifications could be wide-reaching within the police force.