In the late 1930s a sub-genre developed in the American film. The so-called screwball comedies were different from the comedies that had gone before, and to some extent it is a sub-genre that has persisted. The definition of a screwball comedy is not as definite as that for, say, a Western or a Horror film, and whether a given work fits this sub-genre is always arguable. Howard Hawks’s Bringing Up Baby (1938) is an accepted classic in the genre, while Rob Reiner’s Harry Met Sally (1989) is not so clearly an echo of the original group of films so classified.

The original screwball comedies were made in the era between the onset of the Depression and the end of World War II. Ed Sikov offers a definition of screwball comedy that emphasizes the sexual relationships involved, with madcap comedy surrounding the onset and development of romance. Usually, he says, the,,,