Clifford Parker Robertson III (born September 9, 1925) is an American actor with a film and television career that spans half of a century. In addition to his Oscar and Emmy and several lifetime achievement awards from various film festivals, Robertson has a star on the Hollywood Walk of Fame at 6801 Hollywood Blvd. In 1968, he won an Academy Award for his role in Charly.

A serious and talented actor, at his best playing somewhat troubled characters, Cliff Robertson has been a fairly successful leading man through most of his career without ever becoming a major star. Following strong stage and television experience, he made an interesting film debut in a supporting role in Picnic (1955). He then played Joan Crawford (I)'s deranged young husband in Autumn Leaves (1956) and was given leads in films of fair quality such as Naked and the Dead, The (1958), Gidget (1959) and Big Show, The (1961). He supplemented his somewhat unsatisfactory big-screen work with interesting appearances on television, including the lead male role in the small-screen version of "Days of Wine and Roses" in 1958. Robertson could be effective playing a chilling petty criminal obsessed with avenging his father in the B-feature Underworld U.S.A. (1961) or a pleasant doctor in the popular hospital melodrama Interns, The (1962). However, significant public notice eluded him until he was picked by President John F. Kennedy to play the young JFK during the latter's WWII experience in PT 109 (1963). Moving into slightly better pictures, Robertson gave some of his best performances: a ruthless presidential candidate in Best Man, The (1964), a modern-day Mosca in an updated version of Ben Jonson's "Volpone", Honey Pot, The (1967), and most memorably as a mentally retarded man in Charly (1968), for which he won an Academy award for best actor. His critical success with "Charly" allowed him to continue starring in some good films in the 1970s, including Too Late the Hero (1970), Great Northfield Minnesota Raid, The (1972) and Obsession (1976). He also acted in, directed and co-produced the fine rodeo drama J.W. Coop (1972) and, less interestingly, _Pilot, The (1981)_. Since then, he has remained active mostly in supporting roles, notably playing Hugh M. Hefner in Star 80 (1983). More recently he had supporting parts in Escape from L.A. (1996) and Spider-Man (2002).