A supercilious bank inspector is sent to the branch on Walmington on Sea. He is not impressed by Mainwaring using bank premises for Home Guard duty.
When an air raid siren goes off the bank has to be evacuated. When they return there is a hole on the roof. The bank inspector thinks that thieves have tried to raid the bank.
In fact a bomb was dropped, Captain Mainwaring and Sergeant Wilson are left holding it in the vault.
It takes a while for the episode to get going, although it is difficult to get laughs when the two main characters are sweating and under pressure.
It is Walker who brings the laughs, tempted by the money lying about. The rest of the platoon show great loyalty by staying with Mainwaring and Wilson rather than leave them.