Watching Star Trek the original series, episode “Assignment: Earth.” It’s an interesting episode.
The Enterprise intercepts an Earthman beaming through space. They detain him but not for long. He escapes and beams himself to Earth, to an office with a hidden portal with a safe door and a huge computer among other things.
The Earth Space-man is named Gary Seven and he is on a mission to save Earth from a nuclear disaster. A secretary, played by Teri Garr shows up and has no idea what is going on. Capt.Kirk and Mr.Spock, in period costume (fashion of the era of the show), beam down in pursuit of Seven.
A few things mark the episode. “Assignment: Earth” was being developed as a separate series, if it had been picked up the characters would have continued their adventures in their own time on prime time. It was fun to see a young Teri Garr as the secretary. Robert Lansing as Gary Seven is a smooth operator and uses a “servo weapon/tool” for a number of uses. The servo thingy is about the size of a big pen. The episode aired about the time the sonic screwdriver was starting to make appearances on Dr.Who in Britain. As far as I know there’s no evidence to suggest that the people that worked on either series knew of the others’ device.
It’s a fun episode chock full of late 60s cool and doomsday tension.