Tim is feeling upset. The local disco doesn't want him visiting there. Tim can't understand what the problem is — he has the grease for his hair, the light blue shirt, a bathplug on a chain around his neck (as a pendant), tight black skinny trousers and the . Tim is also jealous of John Travolta because he has Livvy and Tim wants her. Indeed, Tim has replaced his treasured photo of Queen Elizabeth II with a photo of Olivia Newton-John (Bill, who had expected Tim to still have a photo of Queen Elizabeth, is shocked at the discovery). Tim thinks that disco is all about the pose — and nothing else. Graeme, surprised, says: "You've seen Saturday Night Fever, haven't you?" to which Tim responds: "certainly not, it's an X-film, I'd be frightened."

Graeme and Bill are accompanying Tim to the disco. Tim is now dressed in his John Travolta-style white disco shirt. Then Bill enters, dressed in evening wear and singing: "My top hat, wearing my white tie, brushing up my tails, my cane, and my taps" (referring to his 'Tap shoes' — with real faucets on the toes of his shoes). When Graeme enters the room dressed up like a ballet dancer, saying: "Bill, take it seriously," Tim is surprised and asks: "Graeme, why are you dressed as a woman?" to which Graeme replies: "What! Three chaps going out dancing together? People would stare at us!" When Tim confesses his inability to dance, Graeme teaches him to do the Disco heave – a dance that Tim believes is Graeme attempting to set him up (until he sees everyone in the disco doing the dance).

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Wikipedia