Shetland's Alison O'Donnell responds to heartbreaking episode 1 reveal

"When it's your friend lying there, covered in blood, it's the personal stuff that really bubbles to the surface. What rushes in is, 'What about her son?' And Tosh sort of wobbles for about five seconds.

"But then she's on the phone to Billy, because you have to. And I think that's something that you learn as a parent. Even when everything's burning around you, you still have to be the person in charge.

"And so she has a very brief moment to be the friend, and then she's got the police hat back on again and she's having to deal with logistics, the practicalities."

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It's yet another test for Tosh, but "what she's shown us season after season is that she's in the right job", added O'Donnell.

"She's someone who's able to do that. She's able to take charge. And that's just what’s required of her, you know? She's just got to get on with it."

The construction site where Annie's body was discovered belongs to her estranged husband Ian, who is also missing and is close friends with Tosh's partner Donnie, which causes conflict in their relationship.

"This one for her is really close to home, too close for comfort," said O'Donnell. "And it's not just Tosh who is affected, it's Donnie. Their relationship is thrown into a bit of jeopardy, so it's a really difficult path to tread.

"One of the defining characteristics of Tosh is that she's got this integrity about the work, she's always going to do the right thing. Even if that is difficult, she'll do the right thing by the case.

"And that's a tricky thing with your significant other because you're saying the case is the most important thing. And actually, I think at some point along the road, she has to stop and take pause. It can't just be as black and white as that."

O'Donnell went on to say that Tosh, for all of her efforts, won't come out of season 9 "unscathed".

"At the conclusion of the series, her relationships are not what they were when the series begins," she said.

Shetland continues on Wednesday 13th November on BBC One and BBC iPlayer. Ann Cleeves's Shetland novels are available to buy now.

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