Margaret Lockwood (Donna Agnes)
Roger Livesey (Captain)
Robert Adams (Mesty)
Hughie Green (Midshipman Easy)
Frederick Burtwell (Mr. Easthupp)
Lewis Casson (Mr. Easy)
Tom Gill (Gascoigne)
Harry Tate (Mr. Biggs)
Desmond Tester (Gossett)
Dennis Wyndham (Don Silvio)

The precocious Master Easy joins the Royal Navy aboard HMS Harpy as a midshipman.

His lofty attitude and difficulty in adjusting to Navy discipline soon gets the young man into trouble.

Unrepentant, he and his young officer friends set about rescuing a girl and her family from Spanish bandits.