Downton Abbey 3 trailer dials up emotion as stars bid farewell in finale

While plot details of the film are limited, the trailer offers some short snippets of what fans can expect, including Dominic West's Guy Dexter in the West End and Michelle Dockery's Lady Mary wearing quite the lavish gown.

A touching tribute is also paid to the late Dame Maggie Smith, with a photo of her character, the Dowager Countess, framed on the walls.

Back in March, a poster for the third Downton film was released, which sees Dockery as Lady Mary, wearing the red gown as shown in the trailer.

Returning alongside Bonneville, West and Dockery for the third instalment are Elizabeth McGovern, Michelle Dockery, Laura Carmichael, Jim Carter, Phyllis Logan, Robert James-Collier, Joanne Froggatt, Allen Leech, Penelope Wilton and Lesley Nicol.

Michael Fox, Raquel Cassidy, Brendan Coyle, Kevin Doyle, Harry Hadden-Paton, Sophie McShera and Douglas Reith will also be return, and they will joined by new additions including Paul Giamatti, Joely Richardson, Alessandro Nivola, Simon Russell Beale and Arty Froushan.

While this will be Giamatti's first Downton Abbey film, he had previously starred in an episode of the series.

Giamatti recently told Entertainment Weekly of his role: "I do something quite important in this [movie]. I was like, wow, this is random, I have a lot to do with the end of this whole series.

"I do something of real significance – good or bad, I'm not going to say! But, I do something that makes a big difference to how everything ends."

Downton Abbey: The Grand Finale will be released in UK cinemas on 12th September 2025. All seasons of Downton Abbey are available to stream on ITVX.

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