Mia Nadasi, the actress who plays Viktoria, was married to episode director Peter Sasdy.
Theresa: [dismissing Edward]: I'm sure you will have great success. You people usually do.
Viktoria: Is membership of the Club of the Damned only available to men?
Sir Charles: To gentlemen.
Viktoria: Why is that, Sir Charles? Don't you like women?
Elizabeth: You may own half the world, Miss Graham - but you do not own my husband or my daughter!
Extras playing uncredited walk-ons in this episode were Michael Lomax, Leslie Weekes, Neville Ware, Katherine Landers and Colin Thomas.
This was the only episode in this series not to be scripted by Robert Muller, its creator. Sue Lake wrote the script from a storyline devised by Muller.