The BBC has released a dramatic first-look trailer for Shetland season 11 – which also marks Alison O’Donnell’s final outing as Tosh.
The clip teases a "historic murder which will forever change the lives of all those connected in the present day".
The synopsis continues: "When a car is pulled from the water, a grim discovery is made – crammed in the boot are the decomposed, skeletal remains of an unknown male. The team’s search to uncover the victim’s identity, begins with a hunt for the vehicle’s owner – a respected, local GP who left the Isles under a cloud of troubled rumours nine years ago.
"As Calder and Tosh dig deeper into the enigmatic GP's state-of-mind and the lives of the loved ones he left behind, the investigation takes them to dark and dangerous places in their quest for the truth."
You can watch it below.
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Tosh is certainly no stranger to demanding cases, but she will be pushed to her limits ahead of her departure.
"These were some of the most challenging scenes I've ever shot for the show," said O'Donnell. "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. Hopefully that doesn't give too much away.
"That's the thrilling side of it, but there were also many more thoughtful scenes with all the important people. It's all in there. I think it's a memorable exit. We'll see!"
Explaining her decision to leave, O'Donnell said: "I've been involved with it for 14 years now... at this point it feels like we've probably explored it enough. 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".
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Recalling wrapping her final ever scene, O'Donnell said: "Our producer Angus [Sharpe] made a speech after we wrapped my final scene but sadly I can't really remember what he said because I was crying, it just came over me.
"It just felt so overwhelming. I think it's going to take me years to fully process it."
But while it's onto pastures new for O'Donnell, it has been reported that Shetland will return for season 12 – although the BBC has yet to confirm that.
Shetland will kick off on BBC One on Thursday 12 November at 9pm.
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