Anti-British agents plan an attack on a Royal Navy ship. Jim Bennett is a sailor who has overstayed his shore leave. He explains he was a boxer and if hit in one side he sleeps for 24 hours but if hit on the other he wakes. Meanwhile, George Blake (Formby) serves drinks to officers in a gentlemen's club. They chastise him for his poor service and say he should join the
Navy. George retires to his room in the club where he chats to his goldfish Egbert. During an air raid George is out with Jim and for various reasons is wearing his uniform. Jim gets knocked out and is trying to "revive" him by hitting him on the other side. The military police spot him and think he is both attacking Jim and that he is absent without leave. From then he is mistaken for the absent Jim. He has borrowed his to go to a
Lock-in at a pub. George is spotted by
military police who think he is
AWOL and escort him back to Naval barracks. He impresses the sailors there with his song "It Serves You Right - You Shouldn't Have Joined" whilst playing
ukulele, and is chosen to play at the "Spick and Span" troop radio concert in London. He meets Pat, a Wren, here, and they start to fall in love. He takes her to a dance and sings "If I Had a Girl Like You" to her. In the same period, he stumbles on the aforementioned pair of Nazi spies using a
taxidermists shop as a front, and foils their plot to blow up a British
submarine, "The Firefly". He also impresses and wins the heart of Pat (Anne Firth), the
Wren he has fallen for. When the real Bennett fully recovers in hospital he panics that he is absent without leave and runs into the two military police who have been harassing the false Bennett. George passes and they give chase. He meets Pat in a car and they think they have escaped, but the group chasing them flag down a police car. They drive to harbour and steal a small launch but the others also steal a boat and the chase continues until George's boat is wrecked. ==Cast==