Also coming on board are former 'Coronation Street' star Julie Hesmondhalgh, BAFTA winner Georgina Campbell, Sarah Parish, Charlie Higson and Mark Bazeley.
David and Olivia will be reprising their roles of DI Alec Hardy and DS Ellie Miller, with Jodie Whittaker and Andrew Buchan also returning as grieving parents Beth and Mark Latimer.
Arthur Darvill also returns as local Vicar Paul Coates, Carolyn Pickles as newspaper editor Maggie Radcliffe, Charlotte Beaumont as Mark and Beth’s daughter Chloe, and Adam Wilson as Ellie’s son Tom.
Not mentioned in the cast is Matthew Gravelle, who played exiled murderer Joe Miller, Ellie's husband cast out of the town after he was cleared of the murder of the Latimers' son Danny.
ITV will be hoping this third series fares better than the second, regarded by viewers as an enormous let-down following the phenomenon created by the first. Series 1 was nominated for seven BAFTA awards and won three, for Olivia Colman, David Bradley and for Best Drama Series.
While the second series disappointed viewers with its focus on Joe's trial, the third series promises a band new case for the police officers, with Alec and Ellie reuniting to investigate a serious sexual assault, and the drama looking at the emotional cost involved to friendships and relationships, put under the harsh glare once again of the investigating police.
According to the series creator, Chris Chibnall, this will be the final chapter for 'Broadchurch'.
“We have one last story to tell, featuring both familiar faces and new characters," he says. "I hope it’s a compelling and emotional farewell to a world and show that means so much to me.”
Chris Chibnall will be moving onto an even larger project following the completion of this third series. He is set to replace Steven Moffat as the show runner for 'Doctor Who' from next year, with his first show set to air in 2018.
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