Mason's distinctive voice enabled him to play a menacing villain as much as his good looks assisted him as a leading man. His roles include the failing actor in the 1954 version of A Star Is Born, a mortally wounded terrorist in Odd Man Out (1946), Captain Nemo in 20,000 Leagues Under the Sea (1954), a suave masterspy in North by Northwest (1959), and Humbert Humbert in Lolita (1963).
Mason died as a result of a heart attack on July 27, 1984 in Lausanne, Switzerland. He was cremated, his ashes eventually buried in, Corsier-Sur-Vevey, Vaud, Switzerland. His old friend Charlie Chaplin is in a tomb a few steps away.