While filming the final scene of the movie, where Michael is revealed to have disappeared after being shot by Loomis and falling off a balcony, Pleasence asked Carpenter if he should do an expression of surprise or an "I knew it'?"
While recording the concluding scene of the film, where Michael is seen to have disappeared after being shot by Loomis and falling off a ledge, Pleasence questioned Carpenter about whether to depict astonishment or "I knew it."