After spending much of her childhood in foster homes, Monroe began a career as a model, which led to a film contract in 1946 with Twentieth Century-Fox. Her early film appearances were minor, but her performances in The Asphalt Jungle and All About Eve drew attention. By 1952 she had her first leading role in Don't Bother to Knock and 1953 brought a lead in Niagara, a melodramatic film that dwelt on her seductiveness. Her "dumb blonde" persona was used to comic effect in subsequent films such as Gentlemen Prefer Blondes (1953), How to Marry a Millionaire (1953) and The Seven Year Itch (1955). Her dramatic performance in Bus Stop (1956) was hailed by critics and garnered a Golden Globe nomination. Her production company, Marilyn Monroe Productions, released The Prince and the Showgirl (1957), for which she received a BAFTA Award nomination and won a David di Donatello award. She received a Golden Globe Award for her performance in Some Like It Hot (1959). Monroe's last completed film was The Misfits (1961), co-starring Clark Gable.
The circumstances of her death, from an overdose of barbiturates, have been the subject of conjecture. Though officially classified as a "probable suicide", the possibility of an accidental overdose, as well as of homicide, have not been ruled out. In 1999, Monroe was ranked as the sixth-greatest female star of all time by the American Film Institute.