Robert Herron was a stuntman who doubled for Jeffrey Hunter in The Cage and later played the crewman Sam in Charlie X and Kahless in The Savage Curtain.
Robert Herron (1924–2021), often credited as Bob Herron, had one of the longest stunt careers in Hollywood. His Star Trek work began with the first pilot, The Cage, in which he doubled for Jeffrey Hunter during Pike's fight with the giant Kalar warrior on Rigel VII.
In Charlie X he played Sam, the crewman in the gymnasium whose laughter at Charlie Evans causes the boy to make him vanish. He also performed stunts in several other episodes.
His most substantial role was Kahless the Unforgettable in The Savage Curtain, the image of the Klingon tyrant created by the Excalbians to fight beside Colonel Green and Genghis Khan against Kirk, Spock, Lincoln and Surak.