Mainwaring's lecture is a total mess due to gas masks. To obtain rationed petrol, Joe convinces Jones to volunteer his butcher's van as platoon car. Alas, after they worked for days to make it fit for the platoon, HQ has it converted to gas. Meanwhile, to Mainwaring's snobbish horror, vulgar grocer Hodges makes his haughty entry as ARP Chief Warden, and rival rooster in town and church hall.