The Day the Earth Stood Still was a science fiction film released during the mid-20th century. The plot centers on a fictional postulation of what Humanity's first contact with an alien race would be like. Although the alien that arrived on Earth was a benevolent ambassador with essentially peaceful intentions, the mass public reacted with hysteria and paranoia at his arrival.
In 2153, after deciding against western movies, Tucker showed the movie to Charles, a Vissian cogenitor whom he'd befriended, knowing that it would be the first movie the cogenitor would watch. After watching the film, Charles asked Trip why Humans were afraid of Klaatu and his android. (ENT: "Cogenitor")
Lawrence Dobkin, who directed the Star Trek: The Original Series first season episode "Charlie X" and guest-starred in the Star Trek: The Next Generation fourth season episode "The Mind's Eye", appeared in this movie, as one of several doctors tending to Klaatu (the latter of whom is the main character in the film). Reginald Lal Singh, who guest-starred in the TOS first season episode "Court Martial", appeared as a scientific delegate in the film.
In Captains' Logs: The Unauthorized Complete Trek Voyages, Michael Piller calls the basic plot of TNG: "First Contact" an homage to this film, only "we're the aliens."
Although Klaatu's mission is to deliver to Earth a forceful warning against "extending your aggression beyond your planet," he asserts that those he represents have no interest in how Humans manage their own affairs. This assertion may be considered similar to Starfleet's Prime Directive.
The Spanish title for the movie is "Ultimátum a la Tierra" (literally "Ultimatum to Earth"), not being known for its original title. However, in the dubbed version of the episode "Cogenitor", Tucker translates the original, literal title ("La Tierra Se Detuvo", literally "The Earth Stood Still"). Later, Tucker explains it is a fiction (commenting, "In fact, the Earth did not stand still"), keeping the literal translation, but adding confusion to a Spanish-speaking audience that might not be familiar with the original title.
The Italian title for the movie instead is "Ultimatum alla Terra" (literally "Ultimatum to Earth"), but, as opposed to the Spanish version, there has been no literal translation in the dubbing, with also the latter dialogue being adapted. (In the Italian version, Tucker states, "Sì, ma è una favola. Non abbiamo mai ricevuto ultimatum," which literally translates to "Yes, but it is a fable. We have never received ultimatum.")