"Wetherby Pond" (Alastair Sim) is the headmaster of a boy's school who really just wants a peaceable life with his miscreant pupils at "Nutbourne" school. It's the war, though, and the useless mandarins at Whitehall decide that he is going to have to share his premises with another school. Thing is, they get all caught up in their own red tape and next thing he finds the intimidating "Miss Whitchurch" on his doorstep, armed with hundreds of girls, luggage, hockey sticks - you name it. They are there and there to stay. Before he can blink, "Pond" and his staff have been outmanoeuvred and his shi... lees die res.