</ref> By the The Cage (Star Trek)|first aired episode, Spock had become greenish/yellow, and was instead from the planet Vulcan (Star Trek)|Vulcan. Leonard Nimoy was cast as Roddenberry saw his guest appearance in ''The Lieutenant'', which he had created and sold as a pilot. Had Nimoy turned down the role, Roddenberry would have approached Martin Landau.<ref>Dillard, p.10</ref>
NBC was concerned about the satanic appearance of Spock, and asked for the character to be dropped. Spock did not originally have the logical manner he would soon develop, this instead being a trait of the character of Number One (Star Trek)|Number One. Roddenberry refused, and Spock was the only character from the first pilot to make it into the second pilot, "Where No Man Has Gone Before (TOS episode)|Where No Man Has Gone Before". This episode presents a more fully-formed Spock, with his trademark logic.<ref>Dillard, p.13</ref> Nimoy liked the character's newly logic-based nature. He said, "This half-human, half-Vulcan being, struggling to maintain a Vulcan attitude, a Vulcan philosophical posture and a Vulcan logic, opposing what was fighting him internally, which was human emotion."<ref>Dillard, p.15</ref>
Back-story
Spock's back-story was not fully developed to start with (even the name of his species changed from "Vulcania... read all