A portion of this episode was filmed in the Bradbury Building in Los Angeles, the same building used as J.F. Sebastian's home in Blade Runner (1982).
This episode won the Writer's Guild award for best screenplay in 1965, the first of four awarded to Harlan Ellison.
Harlan Ellison's friendship with Robert Culp dates from the production of this episode. He found Culp to be very intelligent, quite a contrast to most actors, whom he described as "dips - strictly non compos mentis." When Culp first met Ellison at the Bradbury building location for the film, Ellison introduced himself in a loud voice and told Culp that he wrote the episode just for Culp. Culp also stated that he felt it was one of the best written episodes of television in the history of the medium. Culp indicated that he felt the success of the series and this episode was due to the fact that it was, essentially, a morality play.
Dean Smith, stunt double for Trent, broke both his ankles while jumping down a flight of stairs during production.
There seem to be two versions in existence of the introduction to this episode, one where Vic Perrin says "Sumerican" rather than "Sumerian" and one where he pronounces it correctly. Dreams with Sharp Teeth (2008) shows the latter, Hulu.com the former, and despite the scene during the intro being of New York's Duffy Square, the action actually takes place in L.A.'s Bradbury Building, recognizable as the setting for numerous sci-fi movies.