STAR TREK
TOMORROW IS YESTERDAY

From Wikipedia:

"Tomorrow Is Yesterday" is a first-season episode of Star Trek: The Original Series. It is episode #19, production #21, first broadcast on January 26, 1967, repeated July 13, 1967, and was remastered in 2006 for syndication broadcast on May 5, 2007. The screenplay was written by D.C. Fontana and directed by Michael O'Herlihy.

Overview: The crew of the Enterprise travels back to 1969 Earth and must correct damage they caused to the timeline.

More here.

This one blew me away when I was four years old. I mean, it has Kirk and crew visiting twentieth century Earth, interacting with the US Air Force, like only three years before I first saw the episode! I still have the image, burned forever in my brain, of the Enterprise flying through the blue sky, on the television set my family owned back in 1972. Definitely a keynote memory for me.

But my love for "Tomorrow Is Yesterday" goes beyond simple nostalgia. I mean okay, it's cool to see Star Trek placed in what is more or less our era, but this is a good time travel story, exploring the potential paradoxes and harms which could stem from knowledge of the future contaminating the past--indeed, much of the story is about keeping the Air Force from learning anything about their future visitors at all. And there are some great characters. USAF Captain Christopher is, in his own way, every bit as cool as Captain Kirk. The Air Force security guards are a lot of fun, too. Not the greatest episode of the series, but definitely good.

Alas, CBS appears to have disabled the embedding function for this one, so you've got to go there to see it. But that's okay. Here you go. Really, this is a good one.


Lieutenant Colonel Fellini: I am going to lock you up for 200 years.
Capt. Kirk: That ought to be just about right.

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