BBC crime drama Shetland returns to screens tonight with a gripping new mystery — and the beginning of an emotional farewell for one of the show’s longest-serving stars.
Alison O’Donnell, who has played Detective Inspector Alison “Tosh” McIntosh since the drama first began in 2013, is preparing to leave the series after 13 years.
The Scottish actress has been a key part of the award-winning show throughout its 11 series and remained a familiar face following the departure of original leading man Douglas Henshall in 2022.
Now, O’Donnell will join Ashley Jensen’s DI Ruth Calder for one final six-part investigation set against the dramatic backdrop of the Shetland Isles.
A Dark Mystery Begins the New Series
The latest series opens with the discovery of a car recovered from the water. Inside its boot are the decomposed skeletal remains of an unidentified man.
The vehicle once belonged to Dr Raymond Linden, a respected local GP who disappeared from Shetland nine years earlier amid troubling rumours.
As Calder and Tosh attempt to unravel the mystery surrounding the doctor’s disappearance and identify the dead man, they uncover secrets that could have life-changing consequences for those connected to the case.
O’Donnell has promised that Tosh’s final storyline will be both dramatic and emotional, revealing that some of her last scenes were among the most demanding she has ever filmed for the show.
“These were some of the most challenging scenes I’ve ever shot for the show,” she said.
‘Playing Tosh Has Been the Greatest Gift’
O’Donnell announced earlier this year that she would be stepping away from the role after more than a decade.
Explaining her decision, she said it was not prompted by one particular reason but by a combination of factors.
“I’ve been involved with it for 14 years now and I’ve been so lucky to have been given so many different storylines and challenges and to have worked with so many extraordinary actors,” she said.
“But at this point it feels like we’ve probably explored it enough.”
The actress admitted that leaving was always going to be a bittersweet decision.
“I don’t think I would ever have found a moment to step away that didn’t feel sad and bittersweet, but something in me said ‘leap’, and so I did.”
She has previously described playing Tosh as “the greatest gift an actor could hope for.”
A ‘Wild Ride’ for Tosh’s Final Storyline
Fans can expect a dramatic conclusion to Tosh’s journey, according to O’Donnell.
Asked what viewers could expect from her final storyline, she replied: “A wild ride!”
She revealed that the production involved special sets, a stunt artist and some deeply emotional scenes.
“All I can say is there was a huge amount of work involved — the building of special sets, an incredible stunt artist, and some extremely deep emotional digging,” she said.
While the storyline promises plenty of thrills, O’Donnell said it also includes quieter and more reflective moments with the people who matter most to Tosh.
“The thrilling side of it” is only part of the story, she explained, adding that there were also “many more thoughtful scenes with all the important people.”
“I think it’s a memorable exit,” she said.
An Emotional Goodbye to Her Shetland Family
After spending more than a decade with the cast and crew, O’Donnell admitted that filming her final scenes was an overwhelming experience.
“When something is as seismic as this was, you just can’t really take it in as you’re doing it,” she said. “It’s like trying to look directly at the sun. It’s too big and powerful.”
Instead, she focused on getting through the work while trying to appreciate her final days alongside the people she had grown close to over the years.
On her final day, many members of the crew paid a touching tribute by dressing as Tosh, wearing Fair Isle jumpers and styling their hair in buns.
The show’s producer, Angus Sharpe, made a speech after filming wrapped, but O’Donnell said she was so emotional that she could barely remember what he said.
“I was crying, it just came over me,” she recalled. “It just felt so overwhelming. I think it’s going to take me years to fully process it.”
‘We’re Family and That’s Not Going to Change’
O’Donnell is one of the original cast members alongside Steven Robertson, Lewis Howden and Anne Kidd.
Although saying goodbye to them was difficult, she said their bond would remain long after her departure from the series.
“We’re family and that’s not going to change,” she said.
She recalled a particularly special final day filming on the Isles with Lewis Howden, who plays Sergeant Billy McCabe, and Angus Miller, who plays Donnie.
The group were filming in a beautiful location overlooking the sea when O’Donnell told them it would be her final day shooting in Shetland.
She described the moment as deeply meaningful and said the conversations they shared were ones she would cherish forever.
O’Donnell also praised Steven Robertson, who plays DC Sandy Wilson, describing him as an important source of support.
“He’s been an absolute rock for me in recent times, an emotional guru,” she said.
She hopes the cast will one day reunite in the Isles.
What She’ll Miss Most About Shetland
While leaving the show means saying goodbye to Tosh, O’Donnell will also miss the unique beauty of the Shetland Isles.
She spoke warmly about the landscape and the feeling of being surrounded by nature.
“I’ll miss the magic and the majesty of the place,” she said.
O’Donnell also has fond memories of bringing her family to the islands and visiting places they came to love, including Sands of Sound beach and local gift shops.
But perhaps the hardest farewell will be to Tosh herself.
“She has been a constant companion for over a decade,” O’Donnell said.
The actress said she loved the character’s tenacity, humour, lack of pretension and empathy, adding: “She gave me so much.”
Although she plans to return to Shetland one day, O’Donnell said she may need some time away before she can revisit as a tourist.
In the future, she hopes to bring her children back to their favourite places, see what has changed and reconnect with old friends.
For now, however, viewers have one final mystery to solve with Tosh.
The new series of Shetland premieres on BBC One and BBC iPlayer at 9pm on Thursday, November 12.