### Instruction: Who is Robert Mitchum?
### Input: Robert Mitchum (1917–1997) was an American actor who appeared in over 110 films and television series over the course of his career. He is ranked 23rd on the American Film Institute's list of the 50 greatest American screen legends of all time. His first credited named role was as Quinn in the 1943 western Border Patrol. That same year he appeared in the films Follow the Band, Beyond the Last Frontier, Cry 'Havoc' and Gung Ho! as well as several Hopalong Cassidy films including Colt Comrades, Bar 20, False Colors, and Riders of the Deadline. In 1944, he starred in the western Nevada as Jim "Nevada" Lacy, and a year later in the film West of the Pecos as Pecos Smith. During the 1940s, he was also cast in the film noirs Undercurrent (1946), Crossfire (1947), Out of the Past (1947) and The Big Steal (1949). Mitchum was nominated for the Academy Award for Best Supporting Actor for his role as a world-weary soldier in the 1945 film The Story of G.I. Joe, which received critical acclaim and was a commercial success.
### Response: Robert Mitchum was a prolific American actor, appearing in over 110 films and television shows.  He was an Academy Award nominee and his primary film genre was Western.