Arthur King joins the army, and soon starts fantasising about King Arthur and his knights.

Will Hay, back in his role as a hapless teacher, is hired by a grim school in remotest Scotland. The school soon starts to be haunted by a legendary ghost, whose spectral bagpipes signal the death of one of the staff. Hay, assisted by Claude Hulbert and Charles Hawtrey, has to unravel the mystery before he becomes the next victim.

A hapless fire crew are given the ultimatum: put out a fire successfully or else be sacked. They fail miserably, and their ancient fire engine is stolen by criminals attempting to steal the crown jewels from the Tower of London.

A disgraced school master, Benjamin Twist, is mistaken for a tough prison governor and assigned the charge of a prison for particularly hardened criminals. Believing he is being sent to a school rather than a prison, he celebrates accordingly only to find that his drunkenness accidently lands him on the wrong side of the prison bars. The Governorship is eventually restored to him, and he sets about popularising himself amongst the convicts by turning a blind eye to their shady dealings.

Turnbottom Round prides itself as the village without crime; there has not been an arrest recorded by the local police for years. Unfortunately, this is more to do with the inability of Sgt Dudfoot and his constables Jerry and Harbottle to so much as recognise a crime. With their jobs on the line, the trio attempt to stage a crime of their own, only to inadvertently uncover a smuggling ring and a headless horseman...

A schoolteacher and his pupils visit Paris where they outwit a gang of crooks.

Through the influence of a relative, a hopeless railway employee is made stationmaster the sleepy Irish station of Buggleskelly. Determined to make his mark, he devises a number of schemes to put Buggleskelly on the railway map, but instead falls foul of a gang of gun runners.

Nazi spies are out to destroy a new submarine killer, the "Firefly", being developed by the British navy. A hapless waiter named George, after being rejected for military service three times, finally "joins" when, during an air raid, he is mistaken for a real sailor. He soon unwittingly stumbles into the secret hideout of the Nazi spies trying to destroy the Firefly. Complications ensue.

The Crazy gang invade Nazi Germany !! They accidentally pilot a balloon over enemy territory.