Line of Duty Season 4 Episodes
Season 4 Episode Guide
Episode 1 - Episode 1After 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.
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Episode 2 - Episode 2AC-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.
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Episode 3 - Episode 3AC-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.
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Episode 4 - Episode 4Still 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.
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Episode 5 - Episode 5Roz 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.
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Episode 6 - Episode 6AC-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.
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