"Something Nasty in the Vault" is the fifth episode of the third series of the British comedy series Dad's Army. It was originally transmitted on Thursday 9 October 1969.
Plot
Walker arrives to pay some money into the bank, and a rather posh looking gentleman is standing behind him. As Pike prepares to cash his money, he discovers one of Walker's £5 notes is a forgery. Mainwaring is shocked to learn that the money came from him, and decides to hush it up. As Walker leaves, the posh gentleman introduces himself as Mr West, a Bank Inspector. Mainwaring's face falls. He takes him into the office, where West tells him that his monthly report to Head Office has become irregular. Mainwaring blames it on his Home Guard duties. West is shocked to see a Lewis gun Mk1 perched on the windowsill, and berates Mainwaring for putting the bank in danger. Suddenly, the air raid siren sounds and their meeting is cut short. West is less than pleased when they return two hours later, complaining that it could have been one of their planes they heard. Suddenly, he notices a hole in the roof, and flies into a fit of rage, believing that while they were in the Anderson shelter, someone broke into the bank. As he picks up loose notes, both Mainwaring and Wilson vanish. West searches for them, and is shocked to see a massive hole in the floor, where Mainwaring and Wilson are stranded, clutching an unexploded bomb on their laps. West rushes off to get help, bumping into Jones, who quickly takes charge and puts the bank under martial law. He rushes off to get the rest of the platoon and ring the Bomb Disposal Unit, while Pike and ARP Warden Hodges dither about in the office. Eventually, Jones returns with the platoon, where a brief argument ensues after Mainwaring orders him to get the men out. Initially, Walker agrees with the idea, only to be upbraided for it by an outraged Jones. Jones then asks the rest of the platoon if they want to leave as well, which all the men refuse to do. Walker then tells Jones that he isn't going to leave either. Shortly afterwards, Hodges returns and has a brief argument with Jones as to who is in charge of the situation; this is quickly resolved when Captain Rogers of the Bomb Disposal Unit arrives and takes charge. Unfortunately, both the keys to the strongroom are still under Mainwaring and Wilson's possession, so Frazer uses a fishing rod to yank up one of the keys. Rogers enters the strongroom, and identifies the bomb as a 'trembler'. He exasperates Mainwaring and Wilson by saying he has to go back to GHQ to pick up some special equipment. Jones realises that Mainwaring and Wilson cannot hang on much longer, so he proposes an elaborate plan to remove the bomb from them. They tie the bomb to a piece of rope and decide to pull it up, but in the process, it takes Jones with it. Later, they all have a drink in the pub, and West congratulates the platoon for saving the bank. Mrs Pike rushes in and offers her compliments to Mainwaring and Wilson. West offers to pay for the drinks, but the note he uses is a dud, so Walker pays it with money he nabbed from the bank.
In addition to John Snagge's regular role as announcer and newsreader, John Barron featured as Mr West, Frank Thornton as Captain Rogers, and Elizabeth Morgan as Janet King. Rather than Walker's dud £5 note, Mr West is simply made to wait outside Mainwaring's office. The scene with the platoon refusing to leave was omitted, together with the characters of Privates Godfrey and Walker, and the episode ends with Wilson telling Mainwaring and Jones they should get the hell out of there, the visual gag of Jones getting caught up with the bomb and the pub scene being omitted.
