Caroline and Liam catch a burglar in their kitchen and lock him in a cupboard before discovering he is unpopular old school fellow Dave Tandy. To their surprise he wants them charged for assault and they have to do a deal with him as well as tackling precocious Mega,daughter Chloe's friend who insists they adopt her. Jim and his other son Kevin engage in a dispute over which of them caught a huge fish with Kevin finally getting his own back on his father.
The Flynns host a fortieth anniversary party for Caroline's parents pat and Alan,who have come over from Spain,spouting all the cliches Jim anticipated. When Pat lets slip to Chloe that her parents married because Caroline was pregnant with her the girl sulks in her room but Liam and Caroline convince her that they married for love. Kevin spends the party trying to avoid Amy,with whom he had sex at a funeral,until he realises that they are after the same thing.
When work-mate Julie asks Liam to be her paid personal trainer he sets up a gym in his garage with his sons and Kevin as reluctant clients. However the family have to point out to him that Julie is more interested in his body than his professional skills. Kevin over-reacts to being dumped by a girlfriend and Jim's efforts to mediate do not have the desired effect whilst Liam tires of his mother-in-law's new toy, a Webcam with which she is constantly interrupting him from Spain.
Liam attempts to prove that he is still young at heart by going out drinking every night with Kevin and his football friends but ends up embarrassing them and himself before realising he should act his age. Jim presents Caroline and Liam with a hideous portrait of them that he painted at his art class but,after they have destroyed it,admits he only did it in revenge for their nagging him to take up a hobby. However there is a worse painting to come.
When Ted from next door goes away he gives the house keys to Liam,who cannot resist going in for a snoop. After finding a couple in bed he goes back for a second look but falls and hurts his neck,lying to Caroline that he injured it at work. Kevin,whilst blackmailing his brother to let him run extra Maths,or rather horse race betting,coaching welshes to Caroline,who plays along by insisting Liam sue for compensation - until he confesses. Jim worries that a theft from work many years ago may now come to light and is saved when the firm goes into administration.
When the boiler breaks down the Flynns cannot afford to repair it and have to make economies whilst they shiver. Dean,a boy who wants to date Chloe,says he will mend it if she dates him but Liam decides against it. Meanwhile Caroline helps Jim get a job as a hotel doorman but his over-familiar attitude gets him sacked. He does however offer to pay for the repair of the boiler - though at a price.