I just got though watching an episode of the occasional PBS documentary series “Pioneers of Television,” this one focusing on science fiction. The first part contrasted Gene Roddenberry’s social parables on “Star Trek” with the action-oriented, and later campy, approach of Irwin Allen on “Lost In Space.” The last portion of the show was about Rod Serling and “The Twilight Zone.”

Anyway, I learned a bit of Trek trivia tonight I’d never heard before.

Most “Star Trek” fans, and even many casual viewers, know that the show had two pilot episodes. The first pilot episode starred Jeffrey Hunter as Capt. Christopher Pike, with Majel Barrett (who would later marry Gene Roddenberry) as his first officer. Leonard Nimoy’s Spock was a minor crew member. NBC didn’t like the first pilot, finding it too cerebral, but saw enough potential to commission a second pilot, a somewhat unusual step. By this time, Jeffrey Hunter was unavailable, and so William Shatner was cast as James T. Kirk. Footage from the unaired Hunter pilot was later recycled as flashback sequences in an episode of “Star Trek,” establishing that Pike had been the ship’s captain before Kirk.

That Pike-to-Kirk succession was also utilized by the producers of the 2009 reboot.

Anyway, I knew all of that. What I didn’t know  until tonight was that Shatner was not Roddenberry’s first choice for the second pilot. Roddenberry wanted a different actor, but they couldn’t come to contract terms, and so Roddenberry went with Shatner as his second choice.

Captain James T. Kirk was almost played by … Jack Lord, Steve McGarrett from the original “Hawaii Five-O.”

I can’t even imagine that.

And Martin Landau was the original choice for Spock!