From a "Social Register" family, Stevenson attended Princeton University, but was focused on pursuing an acting career. (His mother had appeared on Broadway and in TV commercials.) At age 20, he made his feature film debut as a 40s prep school student coping with his attachment to his roommate in the film version of John Knowles' novel "A Separate Peace" (1972). He revisited similar territory in the coming-of-age drama "Our Time" (1974) and moved to L.A., making his primetime debut on an episode of "Gunsmoke". After proving to be a heartthrob co-starring with Sam Elliott in "Lifeguard" (1976), he was tapped as the older, wiser Hardy brother. Stevenson hoped to differentiate himself from co-star Shaun Cassidy (who found a second career as a singer) by becoming known as "the one who did the acting". But after the demise of the series, there were few offers. Ironically, perhaps, one of the first to come along was for the ABC TV-movie "The House Possessed" (1981) in which Stevenson was a rock star who has had a nervous collapse. He worked sporadically in the 80s, appearing as a regular on CBS' "Falcon Crest" during the 1984-85 season and as the lead in the short-lived science fiction series "Probe" (ABC, 1988), created by Isaac Asimov. In 1989, Stevenson appeared in the TV movie pilot and first season (on NBC) of "Baywatch", playing a man who chooses to don a bathing suit rather than be a yuppie lawyer. Although he was not part of the cast when the series went into production as a syndicated show, he re-joined "Baywatch" for the 1997-98 season. In the interim, Stevenson began a secondary career as a director, helming episodes of "Melrose Place" and "Savannah".