According to Dhani Harrison, son of Beatle George Harrison, the Beatles were to be in a movie similar to "The Prisoner", written and directed by Patrick McGoohan, but the project fell through. McGoohan was able to convince them to allow their song "All You Need is Love" to be used in the final episode; one of the only times the band permitted their music to be licensed for television.
Was hurriedly produced when Patrick McGoohan was informed the show was being cancelled instead of being renewed for a second season. Because of this, he brought Leo McKern back after 13 months following his appearance in Once Upon a Time (1968). McKern had altered his appearance in the interim and was no longer as hirsute, so McGoohan devised a scene whereby the dead Number 2 would be resurrected by means of a process that required his face being shaved before final resuscitation could be achieved.
In an interview filmed to coincide with the showing of the series on PBS in the United States in 1985, McGoohan said he debated how long to show the face of Number One after Six pulls the mask off, since he didn't want it to be too short or too long. He said he finally just picked a random number of frames, although he could not at the time recall how many it was. He also noted that the very last shot of the series was of him driving his car, presumably of him finally free. It is the very same shot used at the beginning, and some fans have theorized that either it means that Six will soon find himself in the Village again, or that the whole adventure was some kind of hallucination.
Generated controversy when it was originally aired because the last third of the episode was designed to be very obscure and be open to interpretation. It forced Patrick McGoohan, who wrote and directed the episode, to go into hiding for a period of time because he was hounded at his own home by baffled viewers demanding explanations.
According to Alexis Kanner, much of the dialogue and action in this episode was improvised during filming.