This was the last TV acting role to date for Carol Booth.
The theme of urban witchcraft in modern America had become a talking-point about eighteen months before this episode was aired thanks to the success of Ira Levin's novel "Rosemary's Baby" and, more especially, the hugely popular Roman Polanski film version of 1968. The writers may also have been thinking of the 1943 film "The Seventh Victim", directed by Mark Robson.
Glenn Howard: [producing Stephanie's Tarot ring}: There's an ancient Nordic superstition that a murderer will betray himself if he's forced to hold some object from the body of his victim.
Peter: Never heard of it...
Glenn Howard: Well, I guess psychologists would call it a combination of guilty conscience and suggestibility.
Peter: [referring to Adrian Blake]: If he has the supernatural power to detect guilt, then maybe he can hand out punishment, too.
Glenn Howard: Understand this, Peter: I don't put down anyone's genuine beliefs, however far-out they seem. And if you're a true believer in what Adrian practises, then I'm an orthodox druid.
Jason: Your great American family is nothing but a collection of hang-ups, all carefully passed down from one generation to the next.
Peter: Can't get out now. Oh, you could climb the wall, but it's electrified. To keep out prowlers.
Glenn Howard: The police call it suicide. Why does Adrian think it was murder?
Peter: He doesn't think. He knows. He read it in the Tarot.