There isn't much improvisation in film - there's virtually none. The people that theoretically could be good at this in a theater situation don't necessarily do this in a film in a way that will work, because it's much broader on a stage.

In the kind of films that I do, there is an extremely limited number of people that can improvise. The reason the ensemble continues in the movies is because those are the people that can do that kind of work. It's not just an accident those people are in the film.

The truth of it is that people are not going to want to go to improvisational theater if it's not funny. You can succeed in doing all the things you're supposed to do - be truthful to scene - and if it's not funny, I'm telling you that no one's gonna care.

Christopher Guest Quotes