An actor with the real-life name of John Drake appears in this episode. John Drake was the role Patrick McGoohan played in Dangerman. (edit) Patrick McGoohan (Mr. X/Number Six) does not have any dialogue for over twenty minutes in this episode. (edit) This was second last episode of the series filmed. The last was the finale, "Fall Out". (edit) Kenneth Griffith is the final new Number Two. The Number Two featured in "Once Upon A Time" and "Fall Out" is played by Leo McKern who previously appeared in "The Chimes of Big Ben". (edit) Kenneth Griffith (Schnipps/Number Two) would later play the President of the Assembly in "Fall Out". (edit) Along with "Living in Harmony", this is one of only two episodes in which Angelo Muscat (The Butler) does not appear. (edit) Christopher Benjamin previously played the same character (Potter) in the Danger Man episode "Koroshi". This lends credence to the belief that Number Six (Patrick McGoohan) is the same person as John Drake, McGoohan's character on the earlier series. (edit) This is the only episode of the entire series to feature children. (edit) It has been said that this script was originally written for the 'Danger Man' series, but was subsequently used in the tale to the children to display Number Six's past to us. (edit)

Number Two: That one wouldn't drop his guard with his own grandmother! (edit) Dr. Schnipps: (to Mr. X) You're not the Duke of Wellington, are you? (edit) Sonia: (to Mr. X) I love you madly. I love the way the hair curls on the back of your neck. You'll make a beautiful...corpse. I'm going to give you the honour of a superb death. (edit) Sonia: Mountaineering rope. It would hold an elephant.
Number Six: I must remember that next time I go climbing with one. (edit) (Sonia tells Number Six that he will be the first to know when the rocket hits London)
Sonia: Oh, won't that be exciting?!
Number Six: I'll just go to pieces. (edit) Number Six: Goodnight children...everywhere. (edit)

When Number Six believes that he has been poisoned, he must consume a number of different alcoholic beverages as an antidote. The drinks, in order, were brandy, whiskey, vodka, Drambuie, Tia Maria, Countreau, and Grand Marnier. (edit) This is the only episode of The Prisoner to feature children living in the village. (edit)

This episode does not have any allusions. Add some now!