The mischievous schoolgirls hope to get rich quick by betting on a racehorse belonging to a wealthy classmate's father. However, they first have to foil a gang of thieves planning to steal the animal and outwit an undercover policewoman sent to infiltrate the school disguised as a teacher. Comedy based on the late Ronald Searle's cartoons, starring Alastair Sim, Joyce Grenfell and George Cole.

The unruly schoolgirls of St Trinian's are more interested in men and mischief than homework and hockey. But greater trouble than ever beckons when the arrival at the school of Princess Fatima of Makyad coincides with the return of recently expelled Arabella Fritton, who has the kidnap of a prize racehorse on her mind.