"Downton Abbey" stars Michelle Dockery, Dan Stevens and Allen Leech reunited in Los Angeles.
Dockery shared a black and white picture of herself pointing to Stevens, who portrayed her on-screen love interest.
Stevens posted the same snapshot on his own account.
"Dorks," Dockery captioned the photo.
"Should Matthew have a mustache for the #DowntonAbbeyMovie...? Vote below..." Stevens polled his followers.Leech had shared a selfie with Dockery last week following her arrival in Los Angeles.
"Look who's in LA! The Dockmiester General. Soon to be my sister-in-law again. #backtotheabbey," he wrote.
"Since the series ended, fans of Downton have long been waiting for the Crawley family's next chapter," Focus Features chairman Peter Kujawski said.
"We're thrilled to join this incredible group of filmmakers, actors and craftspeople, led by Julian Fellowes and Gareth Neame, in bringing back the world of Downton to the big screen."
The "Downton Abbey" film will feature Dockery, Stevens, Leech and much of the principal cast, although Lily James, who played Lady Rose McClare, recently told People she won't appear in the movie.