Dame Diana is extraordinary as a seemingly chic sophisticated woman who beneath the veneer is a psychotic maniac of staggering malice. The production is fine and all the supporting actors are more than capable but this is Diana Rigg's show all the way, she grabs it by the throat and never lets go. So skillful is her performance that you almost, only almost, feel sympathy for this deranged lunatic. Watching her ever so slowly unravel is a compelling experience. At one time plans had been in place to remake this as a theatrical feature with Glenn Close in the lead and while surely she would have been extraordinary in her interpretation it is impossible to imagine anyone besting Dame Rigg's work, perhaps the film makers realized this and that is why the project never went forward. This is an excellent entertainment, don't miss it!