Which actor appeared in the most Billy Wilder films?

Jack Lemmon appeared in the most Billy Wilder films, collaborating with the director in seven features. Their partnership began with Some Like It Hot in 1959 and continued through Buddy Buddy in 1981.

Lemmon’s Wilder films covered an unusually broad range of tones and characters. He played a cross-dressed musician in Some Like It Hot, an ambitious office worker in The Apartment, and a cynical sports promoter in The Fortune Cookie. Other collaborations included Irma la Douce, Avanti!, The Front Page, and Buddy Buddy.

Wilder valued Lemmon’s ability to move quickly between farce, vulnerability, frustration, and serious drama. The director famously described working with him as a source of happiness, while Lemmon regarded Wilder as one of the central creative figures in his career. Walter Matthau was another major Wilder collaborator, appearing in several films, but he did not reach Lemmon’s total. Marilyn Monroe worked with Wilder twice, and William Holden appeared in four Wilder-directed films.