When Dimanche is orphaned at the tender age of one, Chief Inspector Barry Bullpit advertises for any known relative to come forward. Unluckily for Dimanche, her real aunt does not see the message, but an evil money-grabbing imposter does. Dimanche, heir to an enormous fortune, is sent to live with the dreaded Valburga Vilemile, who tries to rid herself of Dimanche at every opportunity. But her lack of success is partly due to Dimanche's wits and courage, and partly to Polly Pugh, Dimanche's young and pretty nanny, who foils all Valpurga's attempts and helps Dimanche find long-term happiness with her real aunt.