RKO (Radio-Keith-Orpheum) Pictures, has long been celebrated for its cycle of musicals starring Fred Astaire and Ginger Rogers in the mid- to late 1930s. Actors Katharine Hepburn and, later, Robert Mitchum had their first major successes at the studio. Cary Grant was a mainstay for years. The work of producer Val Lewton's low-budget horror unit and RKO's many ventures into the field now known as film noir have been acclaimed, largely after the fact, by film critics and historians. The studio produced two of the most famous films in motion picture history: King Kong and Citizen Kane.