What is line of duty series 4?

Series 4 of Line of Duty aired in 2017 and revolves around DCI Roz Huntley (played by Thandie Newton) and her team investigating a series of murders.

The series focuses heavily on the scrutiny of Huntley's investigation by AC-12, led by Superintendent Ted Hastings. Suspicion arises around whether Huntley is deliberately manipulating evidence to frame a suspect, specifically Michael Farmer.

A key plot point involves the death of forensic coordinator Tim Ifield. The circumstances surrounding his death become central to the inquiry.

The series examines themes of corruption, ambition, and the pressure faced by police officers to solve high-profile cases.

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