Dominic Cooper is set to compete for Ophelia Lovibond's affections in romantic drama Summer In February.
The Devil's Double star will have a love rival in Downton Abbey's Dan Stevens, who will also be an executive producer, in Christopher Menaul's big-screen adaptation of Jonathan Smith's novel.
Dominic is on board to portray acclaimed artist AJ Munnings, with Dan as land agent Gilbert Evans and Ophelia as aspiring artist Florence Carter-Wood in the "true and deeply moving story", played out amongst the backdrop of the Great War.
Production is set to begin in January 2012.
Dan, best known for starring as romantic lead Matthew Crawley in the award-winning ITV1 series, has spoken of his pride of getting the film off the ground on the back of Downton-mania.
"It's led to me being an executive producer on a film I've been trying to make for about five or six years, a film called Summer In February," he has said.
"It's looking very cool and it's a beautiful script and we're very excited about it."