For the first time in TV history, a second pilot had to be submitted to convince the network to run the series. The first pilot, "The Cage" was run later as a two part series with Spock commandeering the Enterprise to take his "former" Captain, Captain Pike, to the planet featured in the original pilot. The actual pilot was not broadcast on television until 1988.

Spock is the only character to appear in both of the pilots, the second one, the one featuring Captain Kirk, was "Where No Man Has Gone Before".

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