Arthur pawns his holidaying wife's jewels to buy a job lot of fridge freezers, though the money was ear-marked for purchasing a fleet of mopeds for the fearsome Pizza Man. When the fridges catch fire, Arthur plans a fake robbery to claim the insurance, though real robbers intervene to spoil his plan. As ever it's Ray who identifies them and allows Arthur to make them pay. However his wife returns from holiday earlier than expected.
Arthur goes to Calais with Dave and Ray to buy cheap booze for the club but their van is broken into and all the drink stolen. Arthur meets an old friend Henry, who takes him to a warehouse to get some more but Henry and his gang are burglars, who flee when the police arrive, leaving only Arthur to be arrested and locked up. He is released after Henry is caught and the trio return to Dover but the Customs officer is suspicious that the van is empty and accuses them of drug smuggling.
Sidney Myers seeks Arthur's help, having been erroneously diagnosed with a fatal illness and asked a skinhead to kill him so his wife got the insurance money and then found the diagnosis was wrong. Arthur takes Sidney to Brighton in Dave's sister's caravan where, after a fraught journey, the caravan burns down. Meanwhile Ray has located the skinhead, who tells him that Sidney really wanted him to kill psychopathic ex-convict Benny the Bosh - the very man who turns up at the Salvation Army hostel where Arthur and Sidney have taken refuge. Fortunately he is a forgiving,...
Whilst his parents, Bert and Doreen, are in Spain, Ray meets Susie, a young woman who claims to be fleeing a violent husband. Arthur leases out Bert's house to her but she is not the market researcher she claims to be and nor is she escaping a violent spouse. She is a high class prostitute and she is wanted by a gang of heavies - as well as the police, who charge Arthur with running a brothel.
Having sold an over-priced and less than roadworthy Austin Allegro to a nun, Sister Angelica, things start to go wrong for Arthur as he attempts to supply equipment to Bjorn, the manager of the Jorgensen stress reduction clinic. He believes that he is being punished for his actions and sends Ray to the convent to fix the car, at a loss to his own wallet. However, when Jorgensen finally arrives from America for the clinic's opening, everything goes well and he considers that he has been exonerated in the eyes of God.
After renting a stall at a business fair, Arthur discovers the joys of corporate entertainment and launches the Willesden Entertainment Consultancy. However, he finds himself at odds with an established company, after the glamorous and enigmatic Vanessa diverts some of its clients to him. This puts both Ray and the consultancy in danger when vicious casino owner Kenton comes looking for revenge.
When Ray's Uncle Brian appears to be suffering from depression, Arthur seeks the advice of Percy Vallins, a successful businessman but known manic depressive, who suggests that Brian is shamming. And indeed he is, as a means of keeping Ray's interfering mother out of his florists' business. Having 'cured' Brian, Arthur then has to call in Detective Sergeant Rogerson when ex-cop Henry Keys, another manic depressive, to whom Arthur has sold a car, locks himself in the Winchester club toilet.
Arthur's sales plummet due to rival dealer Don Gedley so he advertises with Ray's friends on their pirate radio station. Don is a fair man but his violent, greedy son Grant sets out to break Arthur by framing him for driving a car through a shop window. Don agrees to pay Arthur handsomely if he takes the rap but Grant will not be satisfied, requiring Arthur and Ray to team up with Don and the pirates to teach him a lesson.
Arthur is one of several people being targeted by violent criminal Charlie Knowles, who is doing time for armed robbery and wants vengeance on accomplices who got lighter sentences or in Arthur's case, because he sold him the getaway car, which broke down and caused him to get caught. Knowles's outside man Phelan has Arthur framed on a charge of dangerous driving, for which he gets community service but Detective Sergeant Rogerson has his suspicions and joins Ray in exposing the set-up.
Arthur's former employee Cranky Frankie Connor escapes from prison and takes Arthur hostage, demanding to know if his wife Rosie is having an affair with Italian restaurateur Luigi, who has just opened his Mafia-themed eatery Cosa Noshtra. Arthur persuades Frankie to go with him to the Winchester club to discuss things with Rosie but she calls the police and Arthur ends up getting arrested for sheltering an escaped prisoner.