Star Trek - "Assignment: Earth"
Kirk and his Starfleet posse have come back to the swingin' 60s, baby, to witness Mankind on the verge of, like, blowing itself up with nukes or something. Man, that would be, like, a bummer, I'm sure. They cross paths with Gary Seven, a man who really knows how to make an entrance by beaming onto the Enterprise from BFE (which is apparently 1,000 light years in THAT direction). Neither side really trusts the other. Will they save the Earth, or blow it up? Tune in and find out!
Trivial Pursuit fans take note as this episode also served as the pilot for a proposed spin-off series, to be called Assignment: Earth, that would have followed Supervisor Gary Seven and Miss Lincoln as they fought evil. Think of it as James Bond vs. The Outer Limits. Surely this was a better idea than Lancelot Link.