Olivia Colman and David Tennant start filming final series of Broadchurch in Dorset... as ITV confirm Sir Lenny Henry is joining the cast

Its season finale left viewers disappointed when it aired last year.

But the Broadchurch cast were back to business as they began filming for the show's third and final series on Monday.

And this time they were joined by even more familiar faces, as ITV confirmed that BAFTA award winner Sir Lenny Henry and Roy Hudd would be joining the already impressive ensemble.

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One last time: The Broadchurch cast were back to business as they began filming for the show's third and final series on Monday

Meanwhile, Olivia Colman and David Tennant were seen resuming their roles as DS Ellie Miller and DI Alec Hardy on location in Dorset and Somerset.

In the new eight part series, the daring duo will take on a brand new case, as they investigate a serious sexual assault.

Producers have been researching the ins and outs of the plot for a year, and have worked closely with local organisations and police to distill the emotional cost of such a crime to all of those involved and the strain that it puts on friendships and relationships.

Familiar faces: ITV confirmed that BAFTA award winner Sir Lenny Henry and Roy Hudd would be joining the already impressive ensemble

Dream team: Olivia Colman and David tenant were seen resuming their roles as DI Alec Hardy and DS Ellie Miller, while on set in Dorset and Somerset

Writer, Chris Chinball, said: 'We have one last story to tell, featuring both familiar faces and new characters.

'I hope it's a compelling and emotional farewell to a world and show that means so much to me.'

And producer, Jane Featherstone, added: 'Broadchurch has been an important part of my life and I am so delighted and privileged to be working with Chris and the team again as we embark on the very final series.

Drama: In the new eight part series, the daring duo will take on a brand new case, as they investigate a serious sexual assault

Accurate: Producers have been researching the ins and outs of the plot for a year, and have worked closely with local organisations and police to distill the emotional cost of such a crime

Widespread: The dramatic new season will be filmed across Bridport, West Bay, Clevedon and Bristol

'We will return to the town and characters we know so well as they find themselves caught up in a new and compelling story which will test the strength of the community and the people who live there, and will, I hope, be a fitting end to this trilogy.'

Also returning to the cast are Arthur Darvill (Rev Paul Coates), Carolyn Pickles (Maggie Radcliffe), Charlotte Beaumont (Chloe Latimer) and Adam Wilson (Tom Miller). 

While the first series had much of the nation gripped, eager to discover who had killed Danny Latimer, many fans were not as taken with the show's second outing.

Throughout Series 2, viewers had complained that the court scenes were inaccurate, with some on Twitter even labelling the series 'Boredchurch'.

Final attempt: Producers hope the show will leave the air on a high thanks to the new episodes

Emotional farewell: Crew members say the story will test the strength of the community and the people who live there

Toning it down? Viewers struggled to understand David Tenant in the show's last series as they claimed his accent had gotten stronger

Crowd pleaser: The murder mystery attracted an average audience of more than nine million viewers across the two series

Fans had also expressed their disbelief at some scenes, including a kiss between two middle-aged women many had mistaken for sisters, and characters getting table service at chicken restaurant chain Nando's.

Viewers were shocked to see a 'Fifty Shades of Grey' scene in which Lee Ashworth is seen 'strangling' his wife Claire as the pair engaged in a sexual encounter in the ruins of a clifftop barn.

Nevertheless, the murder mystery attracted an average audience of more than 9 million viewers across the two series, including those who watched via catch-up services. 

Up your game: While the first series had much of the nation gripped, eager to discover who had killed Danny Latimer, many fans were not as taken with the show's second outing

Making up for it: Throughout Series 2, viewers complained that the court scenes were inaccurate, with some on Twitter even labelling the series 'Boredchurch'

Acting confused: During Monday's filming David's character frequently looked confused and distraught

Having a laugh: David and Olivia seemed perfectly at ease in each other's company

Back in character: The laughs stopped as soon as filming resumed

Where is it? David could be seen searching for something in his pockets between takes

Hand it over: Eventually he retrieved his mobile phone and handed it to the crew

Matching: Olivia and David wore matching navy blue outfits on set

Sharp: David cut a lean figure in a finely tailored suit, while Olivia elongated her legs in short heels