Stuart was born in Pennsylvania and worked beside his on-screen acting career primarily as a dialogue coach and supervisor in the film business. He coached stars and directed the dialogs for films such as Flamingo Road (1949), The Breaking Point (1950, with William Campbell), The Boy from Oklahoma (1954, with Anthony Caruso), Lover Come Back (1961), A Big Hand for the Little Lady (1966), Point Blank (1967, with Sharon Acker and James B. Sikking), and Ice Station Zebra (1968). Stuart died of cancer in Hollywood, California. He was 89 years old.