Did you know that the cat Marlon Brando was petting in The Godfather's opening scene wasn't in the script? It was a stray that Brando picked up impulsively, and his gentle stroking of the cat's fur offered a perfect contrast to the violent instructions he was giving to his men. Check out the video below for 25 more unscripted scenes that made their corresponding movies all the more unforgettable.
(Screencap via YouTube)