A man is threatend with scandal when he accidentally acquires a stolen diamond.
An insane murderer is on the loose, and gunning for the men who put him away. Will Hay is on the list, and co-opts Claude Hulbert to try and stop him from meeting a grisly end.
Schoolteacher William Potts is the double of a captured German spy, so he is sent to Germany by British Intelligence to obtain the plans of a new secret weapon, causing chaos in a Hitler Youth school in the process.
The fisherman from a Cornish village have a friendly rivalry with the fishermen (and one formidable woman) from a French port. Then war comes and they must all rethink their petty differences.
Comedian Tommy Trinder plays it straight in this tribute to the wartime AFS (Auxiliary Fire Service). The dedicated band who kept the fires of London under control during the blitz and fire bombings of WWII.