When Chambers asked what time it is on Earth, he is told it is twelve noon--a statement he accepts. Evidently the Kanamits have abolished time zones.
Without some kind of comparative work, it is unlikely that anyone could translate an alien language. Even on Earth, ancient languages were impossible to translate without a similar guide (such as the Rosetta Stone). This problem was addressed in the short story upon which this episode was based, but is ignored here, presumably for the sake of brevity.
It's not clear why the Kanamit leaves the "cookbook" in the U.N. chamber in the first place, other then to make sure Chambers has it so he can try and translate it.
The music that plays when Marge reveals her secrets and begins to dance is Debussy's "Claire de Lune."
Robert Foulk is credited as "Robert Faulk" in the closing credits.
In the shot just after they fall after trying to escape, the ballerina is laying with her leg straight out. In the very next shot, she is kneeling in a totally different direction.
Despite the fact that someone can only travel in time for 30 minutes, and it's a major plot point, Rollo returns to his own time after spending a week in 1890.
When Alan Richards first gets into his car, the driver's side window is rolled up. After a quick cutaway, the car is shown again and the window is down.
When the confederate walks by a young Union soldier holding an American flag, the flag appears to have too many stars on it for the time.
At the end of the episode, when Fats misses what would be his last shot, the cue ball is at the spot mark on the table. Then, when Jesse goes to sink that shot after an interruption by Fats, suddenly the cue ball is much farther away.
The shelter's door was made out of wood covered in fake steel.
Elizabeth Montgomery spoke only one word in the episode: "Precrassny", Russian for "pretty".
The female is all alone and been isolated from any civilization for who knows how long, and yet her legs are still shaved.
When Elizabeth Montgomery is in the barbershop, her hair is wet, but when she runs out of the store and into the street because she thinks that Charles Bronson is chasing after her, her hair is dry.
Trivia: This episode begins on June 3, 1962.
When they show a close up of Decruz's shoes in the panel truck, they are polished to a high shine.
The American Territory of New Mexico was not created until 1850, three years after the year mentioned in the opening narration, and in the episode itself. In 1847, it would have been Spanish New Mexico.
The sound effect of the breaking table in the bar begins to play before Dingle has actually hit it
In the bar the newscaster is carrying a microphone with a long rolled-up cord. The cord is not attached to anything, so the mic is not actually plugged in.
When Dingle holds Don Rickles over his head, we can clearly see his face, and it's obviously not Burgess Meredith.
60s, Thrillers, apocalyptic, beings from another world, cultural phenomenon