As an aside, I read a funny little story about how well William Powell and Myrna Loy got along in real life. Somewhere about 1937 or 1938 a magazine ran a nationwide poll to determine the most popular actor and actress in Hollywood. The response to the poll was huge, with Clark Gable and Myrna Loy winding up being the winners.
William Powell finished 4th in the actor's category, and wasn't about to take this lying down. He sent Myrna a long, florist box filled with sour grapes. The attached card read "Congratulations, from William the Fourth".
Gotta love it....... ;-)