Barrhead actor Douglas Henshall returned to the small screen last night as a much-loved BBC crime drama made a comeback.

Douglas has resumed his role as Detective Inspector Jimmy Perez in hit series Shetland, tackling murder cases from past and present on Scotland’s northern-most islands.

Previously based on novels by Ann Cleeves, the most recent season has been written independent of previous material.

And Douglas, who now lives in London, has revealed viewers will be left to wrestle with questions over right and wrong in the crime drama’s fourth season.

He told the Barrhead News: “I think we’re taking on some big subjects in this series. Last series we did too and we were rewarded and we’ve been quite bold this time around as well.

“Whether you think you’re qualified to know who is a good person and who is a bad person – that’s been interesting to explore.”

The six-part series will continue to move at a pace, with the drama demonstrating the dark surroundings of Shetland and the effect this has had on Perez as he deals with the seemingly-wrongful conviction of Thomas Malone, played by Stephen Walters.

Douglas laughed: “Shetland is a lot more violent than he thought it was going to be. People seem to get murdered there a lot.

“When the person you are trying to build a relationship with isn’t interested in helping you, or even helping themselves, then it gets very complicated.”