Jazz-loving, woodship teacher Trevor Chaplin and his girlfriend Jill are on the trail of a saleswoman who mistakenly delivered a set of records that were supposed to be by Bix Beiderbecke.

Jill is detained by the police, Trevor goes in pursuit of a platinum blonde, Big Al reveals some of his secrets, and Sergeant Hobson tries to make sense of it all.

Trevor is at the apex of an emotional triangle, Sergeant Hobson is in trouble, and Jill is taken out to dinner.