After a brief stint as a teenage tennis player, Brown turned to acting in the early 1940s, mostly in B action films. He starred as the young romantic lead in "Our Hearts Were Young and Gay" (1944) and its sequel, "Our Hearts Were Growing Up" (1946), but is best known as Lt. Rip Masters, father figure to a young boy at an Old West outpost in the children's TV series "The Adventures of Rin Tin Tin". (The show ran from 1954 to 1959 and was later syndicated, with new introductions featuring Brown, in the 1970s.) Brown retired from film in the 1960s to become a manufacturer of body-building equipment but returned to the screen with a part in the spoof "Whiffs" (1975). Brown acted under the names James and Jim Brown and is not to be confused with black athlete-turned-film star Jim Brown or soul recording star James Brown.