Following a lecture on the gases the enemy will use, Captain Mainwaring reads a communiqué sent by GHQ, which says that there is insufficient communication between the ARP and the Home Guard, so the new Chief Warden is attending to discuss co-operation. Mainwaring is disgusted to learn from Wilson that the new Chief Warden is that 'common fellow' Mr Hodges. Mainwaring believes that Hodges' occupation doesn't entitle him to be Chief Warden. Wilson agrees by saying that he has dirty finger nails. When Hodges arrives, he and Mainwaring have a brief argument about who should get the church hall every Wednesday evening. Some time afterwards, Walker talks to Jones about his delivery van. He reckons that he should lend it to Mainwaring as platoon transport. Jones is suspicious, so Walker admits that it will help his black market activities, but offers Jones petrol coupons in return. Jones reluctantly agrees. The next day, Mainwaring congratulates Jones and Walker on their efforts with the van. Jones tells Mainwaring that it not only serves as a troop carrier and armoured car, but it also serves as an ambulance. Wilson demonstrates with some of the platoon to Mainwaring, their new embarking and disembarking strategy, which interrupts Hodges' ARP lecture. He demands to know the reason why, and is intrigued to learn that the van doubles up as an ambulance. He asks the men to come down to Saturday's air raid practice and act as stretcher-bearers for the ambulance. Mainwaring concludes the lecture by telling Jones and Walker that the van is being converted to gas. Jones and Walker reluctantly travel to the church hall with a giant gas-bag on the roof. Jones' bayonet accidentally punctures the gas supply pipe and Jones and Walker succumb to the gas. When they recover, they learn that the gas bag is nearly empty. They reach the church hall to find it empty except for Frazer, who tells them that everyone's already at the practice. Frazer decides the gas fire of the Vicar can be used to refill the gas bag. The Vicar interrupts, but Frazer passes it off as filling the Vicar's gas fire. The trio arrive at the practice, and they prepare to load an old man onto the back of the van, but Jones has left the keys at his shop. They attempt to put the old man through the window of the van, while Jones 'borrows' an irate man's bike to fetch the keys. When he returns, they prepare to load the old man into the van, but it drives off before they can fully load him on. After two unsuccessful attempts, the old man gets up off the stretcher, declaring "I'll walk to the flippin' hospital!"
