There’s this Funny Old Movie
It’s called the The Manchurian Candidate, it has an impressive cast, and its plot centers around a brainwashed American politician who is a sleeper agent of The Enemy.
I don’t know why it came to my mind. I barely remember seeing it and I had to look up its plot on Wikipedia. Sorry for wasting your time. Let me try to make it up to you. This one is not old, it’s only kind of a movie, but it sure is funny.