Old Bill has grumbled his way through the trenches of the First World War. Now it is the Second and, envious of his son, Young Bill, he decides to enlist. He finally enters the Pioneer Corps, which is based near his son. When Young Bill goes missing during a raid, Old Bill shows that there's still life in the old dog yet!

An operation of counterfeit five pound notes is discovered at a variety theater, leading to murder during the performance.

In Britain, a man with a shady past uses his antiquities shop as a front for smuggled diamonds but his young shop-assistant starts blackmailing him, leading to murder and to a police investigation.

During early World War II, a Danish sea captain, delayed in a British port, tangles with German spies.

A bookmaker with a fancy for detective work attempts to prevent the execution of a potentially innocent man.