The actor will play DS Sam Casey, a “headstrong young officer with a strong sense of justice brought in to investigate the shooting of DS Matt Devlin (Jamie Bamber)”.

Series 5, shown on ITV this summer, achieved an average audience of 5.6 million and introduced former Doctor Who star Peter Davison to the cast as Henry Sharpe.

The seven-part Series 6 will see the police and legal teams “facing a shocking crime captured on video, up against the clock in the search for a hostage, and exposing a tragic, medical cover-up”. Meanwhile, the past threatens to catch up with Ronnie (Bradley Walsh).

Guest stars will include Tamzin Outhwaite (EastEnders), Toby Stephens (Die Another Day), Eva Pope (Waterloo Road), Luke Roberts and Tim McInnerny (Blackadder).

> Buy the Series 1-4 boxset on Amazon.

Watch the Series 5 trailer…