— Leonard Nimoy (@TheRealNimoy) December 3, 2014

Note that he said “the first” pilot. He’s referring to “The Cage,” written by show creator Gene Roddenberry and directed by Robert Butler, which was presented to — and rejected by — NBC more than a year before the series finally debuted in 1966. Despite being turned down by the network, and featuring a cast almost entirely different from the show fans would come to love later, “The Cage” actually made it to air as part of the first season of Star Trek, with scenes edited into a two-part story titled “The Menagerie” that aired Nov. 17 and 24, 1966.

Although “The Cage” was rejected on grounds of being “too slow” and “too intellectual [with] not enough action,” NBC wasn’t ready to say no to the series just yet, asking Roddenberry to rework the concept and create a second pilot. In the process of reworking, he dropped the entire cast with the exception of Nimoy and brought in William Shatner as the new captain of the Starship Enterprise. A legend was about to be born.

As Star Trek gained popularity, the original version of “The Cage” became popular in its own right; it was screened at fan conventions before being released on home video in 1986 as part of the show’s 20th anniversary celebrations. It wasn’t until 1988 that it finally aired on television, as part of a franchise retrospective titled The Star Trek Saga: From One Generation to the Next.

The official 50th anniversary of Star Trek is 2016 — Sept. 8, 2016, to be exact — but the roots of the entire mythology have already reached their half-century mark. Happy birthday, Captain Christopher Pike, Number One and Dr. Boyce. In some mirror universe somewhere, you went as boldly as Kirk, Spock and Bones, and for just as long.

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