Watch: Trailer Drops for 'Downton Abbey: The Grand Finale'

After 15 years that saw six seasons of television and two well-received feature films, "Downton Abbey" will be shutting its doors for good with a third movie and a "Grand Finale."

A teaser trailer for the upcoming film catches up with the characters of the beloved franchise in the year 1903, 18 years after the show's 1912 beginnings. In that span of story-telling time, World War I, the Spanish Flu epidemic, and significant social change have all taken place.

The new "Downton Abbey" trailer shows snippets of where members of the beloved Crawley family find themselves as the 1930s dawn. "Lady Mary (Michelle Dockery)... navigates London high society, while Lord and Lady Grantham (Hugh Bonneville and Elizabeth McGovern) oversee the Yorkshire County estate," Variety detailed.

"Dockery, Bonneville and McGovern are joined by familiar faces from across the 'Downton Abbey' films and series," the writeup noted, "including Jim Carter, Brendan Coyle, Joanne Froggatt, Phyllis Logan, Penelope Wilton, Paul Giamatti and Dominic West," as well as offering glimpses of "franchise newcomers Joely Richardson, Alessandro Nivola, Simon Russell Beale and Arty Froushan."

The earlier two films, "Downton Abbey" (2019, directed by Michael Engler) and "Downton Abbey: A New Era" (2022, directed by Simon Curtis), continued the story of the Crawleys and their devoted staff, with the first film focusing on a royal visit and an assassination plot, while the sequel uncovered long-kept secrets involving the family's tart-tongued Dowager Countess Violet (regally played by the late Dame Maggie Smith), with a subplot involving a film production taking place at the estate. (Violet Crawley, a franchise favorite, died in that film, and Dame Smith died last year.) The films have been written by creator Julian Fellowes, who wrote or co-wrote every episode of the TV series.

Throughout the series and films, one of the Downton Abbey staff – Thomas Barrow (Robert James-Collier) – has lived as a closeted gay man, but has gradually evolved from a bitter schemer to a more sympathetic (and romantically fulfilled) character.

"As the beloved cast of characters navigates how to lead Downton Abbey into the future, they must embrace change and welcome a new chapter," the film's page on the Focus Features website says.

In a moving moment toward the trailer's end, Bonneville, in character as the patriarchal Robert Crawley, Earl of Grantham, touches the grand manor lovingly, as if in farewell. The distinctive-looking Highclere Castle, located in Hampshire, has stood in for Downton Abbey throughout the life of the franchise.

"Downton Abbey: The Grand Finale" premieres in theaters Sept. 12. Watch the trailer below.