Colonel Hudson holds an auction and since Aunt Peggy cannot get any more credit at Bernie's garage until she pays her bill she and David takes the soft job of driving for him. Hudson's son Duncan discovers that his young mother is having an affair with the family friend Nigel Parker. Parker gets seriously injured in an accident on his way home from a party at the Hudson estate, and when PC Walker conveys the bad news Duncan runs away. Gina and Phil think that Rob needs to get out some more and invite him and Gina's hairdresser Paula out on a double date. But the constables soon get other things on their minds when the entire police station is infected with nits. And they can only have come from PC Younger who has had lollipop duty at the school.