Born to an ambitious stage mother, he is the younger brother of actor Darryl Hickman, who was in movies by the time Dwayne was four. He debuted onscreen in Captain Eddie (1945), and appeared as a child actor in numerous Hollywood films of the '40s. In the early '50s he was a regular on the TV series The Bob Cummings Show, then later in that decade he played the title role of the series Dobie Gillis. In the mid '60s he played leads in several teen-oriented beach films. He retired from acting in 1970 to become entertainment director of Howard Hughes's Landmark Hotel in Las Vegas. In 1977 he joined CBS-TV, eventually becoming a programming executive. Occasionally he has taken acting assignments.