Davis was born in Louisville, Kentucky, and first appeared on television in 1959. In 1971, Davis did the voice-over for the original series of Alias Smith and Jones, starring Pete Duel and Ben Murphy. He also appeared in one of the early episodes as a gunfighter who was killed by Murphy's character. When Pete Duel died suddenly at the end of 1971, Davis was chosen to replace him, playing the same character, outlaw Hannibal Heyes. However, he never achieved the same level of popularity as Duel, and the series ended in 1973.
In 1972 he married the actress, Jaclyn Smith, but they divorced after three years.