Goodfellas

The “you think I’m funny?” scene was based on a story that Joe Pesci acted out for Martin Scorsese. While working in a restaurant as a young man, Pesci once told a mobster that he was funny and the mobster became very angry. Scorsese allowed Pesci and Ray Liottato improvise the scene. He did not tell the other actors in the scene what would happen because he wanted their genuine surprised reactions.