The film is set at Narkover School, where headmaster Doctor Alec Smart (Will Hay) becomes involved in the disappearance of a valuable necklace.

The setting is loosely based on the works of Beachcomber, where Narkover is a school specializing in gambling and extortion, and the headmaster is a "Dr Smart-Allick".

Narkover proves to be a breeding ground for young criminals, who prefer to spend their time playing cards rather than taking classes.

He gets off on the wrong foot with Colonel Crableigh but, in spite of Smart's obvious incompetence, Lady Dorking immediately takes a shine to him.

After trying, and failing, to persuade him to give it back Smart takes it and hides it in a jewellery box due to be presented to Lady Dorking at the dinner..

The role of the bumbling schoolmaster, which he had first developed in his 1920s music hall act, would be reprised in another two of Hay's films, Good Morning, Boys and The Ghost of St.

Hay had previously appeared in two Pinero adaptations Those Were The Days and Dandy Dick, and a comedy revue show as the incompetent head of a broadcasting service in Radio Parade of 1935.

[4] Based on this film, an Australian radio show was made called Fourth Form at St Percys, which quickly changed its title to Yes, what!