Mainwaring is under orders to be more cooperative with the A.R.P. wardens. A task that's made very difficult by their newly appointed Chief. Walker strikes a deal with Jones to make it easier for him to carry rationed goods without being stopped by the police - he is to let the platoon use his butchers van as a troop carrier and ambulance by day and let Walker use it by night. He bribes Jones with the promise that Jones will receive petrol coupons for it. Unfortunately things don't entirely go to plan... (thetvdb.com)