Shetland is officially returning next month, with the BBC confirming that Season 11 will begin on Thursday 12 November at 9pm on BBC One. Ashley Jensen will return as DI Ruth Calder alongside Alison O’Donnell as DI Alison ‘Tosh’ McIntosh, although the new six-part series will be an emotional one for longtime viewers as it marks O’Donnell’s final season after playing Tosh since the drama began in 2013.

The new investigation begins when a car is pulled from the water and skeletal remains are discovered inside the boot. Calder and Tosh’s search for the victim’s identity leads them to the vehicle’s owner, a respected local GP who left Shetland nine years earlier following a series of troubling rumours. As the detectives begin looking into the GP’s past and the people he left behind, the case develops into an investigation surrounding a historic murder that the BBC says will change the lives of those connected to it in the present day.

Steven Robertson will also return as DC Sandy Wilson, alongside Samuel Anderson as Procurator Fiscal Matt Blake, Steven Miller as Rev Alan Calder, Anne Kidd as Cora McLean, Angus Miller as Donnie, Conor McCarry as PC Alex Grant and Eubha Akilade as PC Lorna Burns. Lewis Howden will also be back as Sergeant Billy McCabe following the uncertainty surrounding his future at the end of Season 10.

New additions to the cast include Christine Bottomley, Kevin Harvey, Stella Gonet, Gregor Fisher and Gavin Mitchell.

O’Donnell announced in June that Season 11 would be her last as Tosh, bringing her time with the character to an end after more than a decade. Speaking about leaving the series, she described playing Tosh as “the greatest gift an actor could hope for”, adding that being able to stay with the character as she grew over the years had been “such a rich and special experience”.

For CultureCues, Tosh leaving is definitely going to be an emotional one. Alison O’Donnell has been such a huge part of Shetland from the beginning, and after more than a decade with the character, it will be sad to see her go. I actually worked briefly as a runner on the show years ago, so there is a little extra nostalgia attached to this one for me, but O’Donnell has had an incredible run as Tosh and has been brilliant throughout. The new case already sounds like a strong mystery for Calder and Tosh to take on together, and I am really looking forward to seeing how her final story plays out.

Shetland Season 11 begins Thursday 12 November at 9pm on BBC One and BBC iPlayer.

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