Pernell Roberts

Pernell Elven Roberts, Jr. (May 18, 1928 – January 24, 2010) was an American stage, movie and television actor, as well as a singer. In addition to guest starring in over 60 television series, he was best known for his roles as Ben Cartwright's eldest son, Adam Cartwright, on the western series Bonanza, a role he played from 1959 until 1965 — and as chief surgeon Dr. John McIntyre, the title character on Trapper John, M.D. (1979–1986).