10 Best Star Trek Cold Opens
4. You Know Why I Have Come, Captain? (The Menagerie, Part 1)
The Menagerie was the Original Series' only two-part episode, and effectively serves as a clipshow. The scenes that are re-used from The Cage, the first pilot of the show, serve to tell the story of Spock's relationship with Captain Christopher Pike, Kirk's predecessor.
The episode opens with Kirk, Spock, and McCoy beaming down to Starbase 11, following a summons from Starfleet. The first hint of what's to come drops when Crewman Piper reveals the base sent no such summons - leaving the officers confused as to why exactly they're present.
We are introduced to both Commodore Mendez and then Fleet Captain Pike - horribly crippled, and confined to the now-infamous chair, complete with blinking lights. This opening sets up a terrific mystery, though it truly succeeds in the reveal that Spock, of all people, is the one responsible for the duplicity. He faked the signal so that the Enterprise would arrive. Ignoring Pike's repeating lights, he promises to help his former Captain in the only way that he knows how.
This was Spock. Spock! There was no crewman or officer more dependable, none more trustworthy, and here he was admitting to treason and mutiny. Though precious little details were revealed before the opening credits, this remains one of the most intriguing scenes in the entire run of the Original Series.