Real reason Celebrity Traitors star Mark Bonnar quit Shetland after 10 years

Mark Bonnar, best known for his role as Duncan Hunter, Cassie's biological father in the popular BBC series Shetland, has been a staple of the show since its inception.

However, after seven seasons, the 56 year old actor decided to bid farewell to the series, citing a desire to explore new roles.

The end of the sixth series saw viewers gripped by the predicament of Jimmy Perez and Duncan, who found themselves embroiled in controversy over their involvement in Donna Killick's death.

Donna, suffering from cancer, had requested Duncan's assistance in ending her life, a request he complied with. However, this was all part of a revenge plot by Donna, who believed Duncan had betrayed her following an affair years prior.

In a letter to her solicitor, she claimed that Duncan had coerced her into suicide, reports the Daily Record. To further complicate matters, Donna implicated Jimmy in her death. Upon discovering the letter, Duncan chose to turn himself in, leading to his arrest.

Jimmy, too, found himself in hot water, resulting in his own arrest. In the seventh series, Jimmy's suspension from the police force was lifted, allowing him to return to duty before his eventual departure from the show.

However, fans were dealt a blow when Duncan announced he would not be returning to Shetland after being released from prison, expressing a desire to start anew.

"There's plenty that think I let Donna off the hook," he admitted candidly, resigned to the fact that he would have to uproot his life and start over.

After his departure, Mark featured on ITV's Lorraine where the presenter enquired whether audiences have witnessed the final appearance of Duncan Hunter.

Mark responded: "Possibly, yes it's all changed, Ashley is starting. She's taking over from Doug which I think is great, great casting love Ashley."

Discussing the enduring BBC drama, the 54 year old informed Lorraine of his affection for Shetland, where he performed for ten years.

He added: "It was a huge part of my life for 10 years and a great joy to do. Pastures new it's very exciting to see what Davy and the rest of the team come up with."

The actor is currently taking part in the fresh celebrity version of BBC Traitors alongside famous faces including Alan Carr, Stephen Fry, and Kate Garraway.

Reflecting on his involvement, he recently commented: "It's so intense - you have no phone, so all you think about is the show.

"The line-up was pretty starry. Stephen Fry has been omnipresent in my life - I watched Blackadder growing up - and I loved chatting to Jonathan Ross about Nirvana."

Mark proceeded to disclose to The Sunday Times that the participants now belong to a WhatsApp chat as he noted: "It's mad being in a Traitors WhatsApp group with them all."

You can catch up on Shetland on BBC iPlayer