BBC One has unveiled a new look at the fourth season of Line of Duty.

The one-minute trailer introduces Westworld star Thandie Newton as AC12’s “most devious opponent yet”, DCI Roz Huntley.

Six new episodes of the police corruption drama began filming in Belfast last September, with returning regulars Martin Compston, Vicky McClure and Adrian Dunbar joined by Jason Watkins (Being Human), Lee Ingleby (The A Word) and Royce Pierreson (Our Girl).

Pre-order Season 4 on DVD on Amazon here.

Watch the new trailer…

The official synopsis reveals: [Season 4] begins with Roz and her team in the thick of a career-defining case, Operation Trapdoor. Under intense pressure to catch the culprit and prove herself to her superiors, and facing conflict with her colleague, Forensic Coordinator Tim Ifield (Jason Watkins), it’s not long before AC-12 decide to probe her handling of the investigation. A mother of two and wife to husband Nick, (Lee Ingleby), Roz will do anything to stop her life unravelling. Anything.

“Determined to uncover the truth, Detective Sergeant Steve Arnott (Martin Compston), Detective Sergeant Kate Fleming (Vicky McClure) and Superintendent Ted Hastings (Adrian Dunbar) must work together to tackle their most devious opponent yet. They are aided by PC Maneet Bindra (Maya Sondhi) and newcomer Detective Constable Jamie Desford (Royce Pierreson).”

Line of Duty launched on BBC Two in June 2012 and the third season concluded last April with 5.6 million viewers.

Buy the complete Season 1-3 box set on Amazon here.

A fifth season was also commissioned last year.

Are you looking forward to Season 4? Let us know below…