In 1955, Kevin and Faith Carlson are travelling through the country when they see a meteorite strike over the next hill. On investigation, they discover an alien spacecraft manned by insectoid beings. The Carlsons race to the nearest town to report what they've seen, but the local sheriff insists that a military plane has crashed. The sheriff takes the Carlsons back to the impact site, where they find a team of U. S. Army scientists combing through a wrecked airplane. Kevin notices that the hands of the army personnel are all deformed in the same unusual way, and so are the sheriff's. He and Faith quietly leave the site and return to town, but they cannot convince anyone that something strange is happening.

When they try to leave the town, they are stopped by the combined efforts of the alien spacecraft and the townspeople. The townspeople reveal that they and the Carlsons are aliens, and that this is a training simulation of an invasion of Earth. However, some of the aliens suffered memory loss and forgot their roles, and the "Carlsons" were among those. The sheriff says he will get the pair back on track.

Some time later, a young man is traveling along the same country road. He also sees an alien spacecraft. He races to the nearest town to report it, but is dissuaded by the local sheriff, who claims that it was only a military aircraft. The sheriff has the face of Kevin Carlson.

The name of the town is an homage to Charles Beaumont, writer of many of the original Twilight Zone episodes. There are also other references scattered throughout the episode, such as saying the meteor was near Willoughby, which is a reference to an original Twilight Zone episode. There's another reference to a town named Matheson, for Richard Matheson, a noted science fiction author and frequent contributor to the original Twilight Zone. The term "Bradbury rays" honors sci-fi author Ray Bradbury, and a line about "giant ants and tarantulas" brings to mind the movies Them!, Tarantula and Earth vs. the Spider. Them! is referenced again in the name of the general store: Johnson's; in Them!, Gramps Johnson was an early victim of the giant ants. Other classic alien-invasion movie tropes abound: as they depart their saucer, the aliens are carrying large seed pods, an obvious reference to Invasion of the Body Snatchers. When in human form, their inability to bend their pinky finger is reminiscent of the 1960s television series The Invaders. Even the character of the astronomer Dr. Carlson could be taken to refer to the astronomer John Putnam played by Richard Carlson in It Came from Outer Space (who also witnessed a UFO crash-landing in the desert).

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