Carole Lombard was a devoted Democrat, while Robert Montgomery was a Republican. During breaks in filming, Lombard made a point of running into the studio parking lot and putting FDR re-election bumper stickers on Montgomery's car.
Alfred Hitchcock decided to direct this film, because of Carole Lombard's request. This was one of the very few films where Hitchcock wasn't involved in the scripting process. Since Hitchcock really didn't understand the type of people who were portrayed in the film, all he did was to photograph the scenes as written.
Carole Lombard, in order to twit Alfred Hitchcock and generate publicity about his comment that "actors are cattle", set up a miniature cattle pen on the set. The pen held three heifers, each emblazoned with the name of one of the three stars.