Q. In what films did an actor break character somehow but it got left in the film?
answered by Jack Connolly
In When Harry Met Sally, there’s a scene where Harry tells Sally to say “I’d like a piece of pecan pie” in a funny voice. Meg Ryan briefly looks surprised and glances away from Billy Crystal, this is because Crystal ad libbed the line and Ryan looked to the director to see what she should do (he signalled to keep going).
In Alien Resurrection there’s a scene where Sigourney Weaver throws a basketball behind her and scores a basket. They assumed it would be a special effect, but, on one take she really did make the basket purely by chance. Ron Perlman has a look of complete surprise on his face and looks over his shoulder, that’s because no one expected her to do it and it was not in the script.