They settled into a comfortable pattern of working with one another, Hepburn considering every possible nuance of a given scene while Tracy gently heckled her from the sidelines. “I think he was so steady,” she said, “and I was so volatile, that we exasperated each other. And we challenged each other, and that was the fun of it.” When John Chapman visited the set on September 12, Hepburn was at a rostrum rehearsing a speech, while Tracy was sitting out in the audience, haw-hawing loudly and doing his best to throw her off. “We are told that this is the big new friendly feud. Spence and Miss H. had never worked together before, and each at first was a little in awe of the other; but now they are in the happy Hollywood state of amiable insult. ‘We will now pause,’ announces Tracy, ‘while Miss Hepburn rewrites the script.’”

(Spencer Tracy: A Biography by James Curtis)