It shows the home of the Crawley family being made up with fresh sheets, a servant's bell being rung and the staff dutifully lining up outside.
A lone motorcyclist is seen approaching as the ITV hit's iconic theme music plays, with viewers being treated to soaring shots over the great house.
The trailer doesn't give fans all that much to go on, but the short glimpse of flag-waving revellers and a very 20th-century vibe points to it being set at the end of the First World War.
All the original cast will be returning for the big-screen outing, including Michelle Dockery as Lady Mary, Laura Carmichael as Lady Edith and Hugh Bonneville as Robert Crawley.
Joanne Froggatt is also appearing as Anna Bates, with Elizabeth McGovern as Cora Crawley.
There are also a number of new additions, including Harry Potter star Imelda Staunton and Killing Eve's David Haig, who plays a sworn enemy of the Crawley family.
However, Lily James isn't coming back as Lady Rose MacClare, with the character having moved to New York.
Downton's creator and writer Julian Fellowes has written the screenplay, with Michael Engler, who was in the charge of the last Christmas special in 2016, on directing duties.
It was recently confirmed that the movie will be released on 13 September next year, with a US release the following week.