Line Of Duty

Police anti corruption unit AC12 return for another thrilling investigation. Sergeant Danny Waldron (Daniel Mays) and his armed response team shoot dead a hardened criminal, but soon cracks appear in their story. What are they hiding?

After the shooting at the drugs house, DC Kate Fleming (Vicky McClure) uses her undercover role to increase the pressure on Danny Waldron's armed response unit. Meanwhile an old AC12 investigation comes under legal scrutiny.

DS Steve Arnott (Martin Compston) believes Danny Waldron compiled a list of his childhood abusers. But while DI Cottan (Craig Parkinson) is commended for cracking the Waldron case, the spotlight falls on Arnott's questionable conduct in a previous enquiry.

Fresh testimony puts AC-12 back on the trail of the Caddy, a corrupt officer with links to organized crime. But new disturbing evidence suggests the Caddy may reside within AC12.

AC12's loyalties are divided when DS Steve Arnott (Martin Compston) is suspended from duty. With his career in jeopardy, Arnott turns to an unlikely source for help.

DS Steve Arnott is arrested on suspicion of murder but continues to protest his innocence.

Does DC Kate Fleming's undercover operation hold the key to Steve's guilt and the identity of the Caddy?