Written by Ben Kaplan, "Captain of the Gate" will follow the U.K. Prime Minister's rise to power and defense of Britain against Adolf Hitler's Third Reich.
Sierra/Affinity will finance the $20 million picture, which is produced by Cameron Lamb and Damon Lane.
As previously reported, Spacey is also set to release "Now: In The Wings On A World Stage," a new documentary film about his experience playing Richard III for the Bridge Project.
He will self-distribute the 90-minute film, which takes its title from the first lines of Richard III, "Now is the winter of our discontent." It can be pre-ordered now at KevinSpacey.com.
