Trivia: This episode was not shown in the initial U.S. airing of "The Prisoner" on CBS. There was speculation that its pacifist, anti-violence moral might have been construed as a Vietnam War protest, but the network's reason for censoring the episode has never been disclosed.
Trivia: When the Captain Scarlet series was sold to TV broadcasters, ITC (who had backed and then marketed the series) issued a "recommended broadcast order". This was not always the same order as the episodes had been made. Episodes 1 to 4 were made and broadcast "in sequence", but from episode 5 this no longer applied. Episode 11 ("Avalanche") was the 5th to be broadcast, swapping places with the episode "Point 783" which was the 5th to be made, but the 11th to be broadcast.
Trivia: Dabbs Greer played an alien disguised as a Minister in this episode. Later he would play Reverend Alden in "Little House on the Prairie."