Jack Lemmon (1925–2001) and Walter Matthau (1920–2000) were a pair of American male actors[1][2] who starred in ten films together,[3] co-starring in eight of them.
In addition, Lemmon directed Kotch (1971), which starred Matthau (and had an uncredited cameo by Lemmon).
Off-screen, they were best friends,[1][3] though their characters constantly clashed on-screen.