Los Angeles, California (CNN) -- Actor Pernell Roberts, who played the eldest Cartwright brother in TV's "Bonanza," died at his Malibu, California, home Sunday at 81, his lawyer said.
Younger TV viewers may remember Roberts from the lead role in "Trapper John, M.D.," a medical drama that aired on CBS for seven years, ending in 1986.
Roberts spent the first decade of his acting career on stage -- including Broadway -- before he was cast in 1959 as Adam Cartwright, the handsome and smart son of rancher Ben Cartwright (Lorne Greene.)
His character was serious and introspective, in contrast to younger half-brothers Hoss (Dan Blocker) and Little Joe (Michael Landon).
Roberts left the popular western after the end of the sixth season in 1965, although "Bonanza" stayed in production for another eight years. While the show's storyline kept open the possibility of his return to the Ponderosa ranch, Roberts never did.
He never gained much of a foothold in film, but stage acting kept Roberts busy for more than a decade.
His role of Dr. "Trapper" John McIntyre -- starting in 1979 -- was a spin-off of a character from the hit TV comedy "M*A*S*H."
Roberts played the balding physician working in a San Francisco hospital nearly three decades after he returned from the Korean War.
His last regular TV job was in 1991 when he was host of the short-lived ABC police anthology "FBI: The Untold Stories."