Tootsie
Now, this film starred both Dustin Hoffman and Bill Murray so basically it was a guarantee hit. Even though Hoffman was the lead, Bill Murray was an outstanding supporting actor as the roommate named Jeff. Knowing about Murray’s knack for improvisation, director Sydney Pollack let him invent a monologue for the party. There’s no need to tell you that his resulting speech was impeccable. Oh and the whole cast never knew what was coming, which makes it all the better!

Tootsie
The Third Man
Yes, Orson Welles became a film industry legend, but did you realize he often improvised? While acting in The Third Man, Welles invented, “In Italy for 30 years under the Borgias, they had warfare, terror, murder, bloodshed. They produced Michelangelo, Leonardo da Vinci, and the Renaissance. In Switzerland, they had brotherly love, five hundred years of democracy and peace. And what did that produce? The cuckoo clock.”

The Third Man