Stuart played supporting or minor roles in such films as
A Yank in the R.A.F., where he played Wales,
Sword in the Desert,
Designing Woman,
Assault on a Queen,
Morituri,
Doctor Dolittle. as well as in other television shows. He appeared in Red Skelton Show for the period of over 16 years. His most notable role was in film
The Sound of Music, which won five Oscars. He played the butler of captain
Georg von Trapp. In the beginning of the film, Maria mistakes him for the captain. He was recommended by another member of the film's team and was a familiar face to director
Robert Wise, who offered him the role shortly before the start of the filming in March 1964. In her memoir
Forever Liesl: A Memoir of The Sound of Music,
Charmian Carr described him as "a marvelous character actor, very reserved", and being part of the "British group" of actors on the set. ==Filmography==