After studying acting in New York at the Lee Strasberg Theatre Institute and privately with Marcia Haufrecht, Buchanan's first major daytime role came in 1986, when he joined the cast of General Hospital in the role of Duke Lavery, whom he portrayed until 1989. After leaving the role of Lavery, Buchanan appeared in roles on prime-time series including It's Garry Shandling's Show as Ian McFyfer from 1988 to 1990, and Twin Peaks as Dick Tremayne from 1990 to 1991.