Robert Conrad, a television tough guy best known for his lead role in the mid-1960s series “The Wild Wild West,” died on Saturday at his home in Malibu, Calif. He was 84.

The cause was heart failure, Jeff Ballard, a family spokesman, said.

Mr. Conrad’s fearlessness and good looks served him well in “Wild Wild West” and many other shows, though he found the most satisfaction in some later, meatier roles, like the fur trader he played in the mini-series “Centennial” in the late 1970s.

He was also well served early on by his ability — at least by the not very rigorous standards of the late 1950s — to affect an ethnically ambiguous character. In one of his earliest roles, he had a bit part as an Indian.

Image Mr. Conrad starred in the 1968 Western “The Bandits.” Credit... LMPC, via Getty Images

“I had to get shot by the good guys and fall off a horse, which I did successfully, and that established me as having enough talent to do stunts,” he recalled in an oral history recorded in 2006 for the Archive of American Television, “so when there was a speaking role and a stunt associated with that speaking role, they’d hire me, because you got two for the price of one.”