"Commonplace, if somewhat grim, unsocial event known as a necktie party. The guest of dishonour - a cowboy named Joe Caswell. Just a moment away from a rope, a short dance several feet off the ground and then the dark eternity of all evil men. Mr Joe Caswell, who when the good Lord passed out a conscience, a heart of feeling for fellow men, must have been out for a beer and missed out. Mr Joe Caswell, in the last quiet moment of a violent life." - Rod Serling, opening narration.

Things didn't quite happen the way this episode's opening narration would have you believe. Joe Caswell, who was to be hung for shooting a young man in the back (one of at least 20 victims, we would later be told), indeed dangled from a rope for some time. As those executing his sentence turned away briefly, however, Mr Caswell somehow vanished. The rope hung empty.

Waking up in an experimental lab in New York City, at a future date, it became known that Joe had been saved by a time altering device. The scientist who unknowingly rescued him from his fate began to realise some of the criminal's primal leanings, expressing in his own dictation that he had concerns about unleashing the stranger upon a civilised 20th Century population.

The scientist, Professor Manion, confronts Caswell about the rope burns on his neck and makes the decision to try to send the monster back to the point of time from which he had been plucked. In the ensuing struggle, however, Manion is critically wounded. Taking the opportunity to escape from his confinement, Caswell dashes out onto the streets of modern New York, where flashing lights, noisy technology, crowded walkways and heavy traffic greet him impartially.

Caswell finds his sudden introduction to modern civilisation too confronting for comfort and after destroying a phone booth, jukebox, television and some other mod cons, he races back to the Professor's apartment looking for help. When he arrives there, he finds that his earlier blow killed the Professor. Caswell is not without company, however.

A thief, Paul Johnson, believing the open apartment to be empty, greets Caswell with a gun. The two eventually clash and the thief manages to murder the cowboy through strangelation. With Caswell out of the picture, the curious Paul Johnson starts poking around the apartment, triggering control knobs as he goes. When he consequently steps into the time machine, it activates and sends the thief back to the same moment in time as from which Caswell was rescued. The main finds his just desserts, by appearing with his neck in the rope that was to kill Caswell. Justice has spanned time to claim both criminals.

"This is November 1880, the aftermath of a necktie party. The victim's name, Paul Johnson, a minor league criminal and the taker of another human life. No comment on his death, save this: Justice can span years. Retribution is not subject to a calendar. Tonight's case in point, in the Twilight Zone." - Rod Serling, closing narration.