Line of Duty — Series 4
6 episodesFirst aired 26 March 2017
The fourth series sees AC-12 facing their most devious opponent yet! Under pressure from her superiors, DCI Roz Huntley charges a young man with a series of murders after months of fruitless investigation, but is he guilty? The Chief Forensic Investigator has doubts and turns to AC-12.
E1Episode 1
8.1Mar 201758m
DCI Roz Huntley is under intense pressure from her superiors to apprehend a serial murderer after months of fruitless investigation.
E2Episode 2
8.1Apr 20171h
AC-12 crank up their investigation into Operation Trapdoor. Kate makes progress in her undercover role.
E3Episode 3
8.4Apr 20171h
As AC-12 wrestle with the new forensic evidence casting doubt over Tim Ifield, Kate is approached by another woman claiming to have been assaulted by Michael Farmer.
E4Episode 4
8.4Apr 201759m
Roz's husband Nick is brought in for questioning by AC-12. But while Nick denies any involvement in Steve's attack, his suspicions about Roz mount.
E5Episode 5
8.2Apr 201759m
DCI Roz Huntley struggles to allay her husband's suspicions. AC-12 find a new angle to pursue their case against her.
E6Episode 6
8.8Apr 201758m
While Nick Huntley faces lengthy questioning, AC-12 remain convinced of Roz's involvement.
