While spending a weekend in York, schoolboy Yo-yo's ring is stolen by Mr Vanilla, a forty stone jewel thief, so he gathers together, among others, Lily Gusset, the reverse drag-artist, Mrs Lollipop, bed-ridden these forty years, Baby the talking blackbird, the custard-pie flinging Lettuce Brother clowns, an angry ichthyosaur, a weed and a pebble, a copper named Kipper, a professional Scotchman named Wee Jocko McTavish and the severed head of the Ninth Earl of Northumberland in a quest to retrieve it.