Middle-class couple June and Terry Medford arrive at their new house in Elm Tree Avenue, Purley, to decorate before moving in - though the wallpaper keeps peeling off, due to Terry's incompetence. After a visit from the couple next door, Brian and Tina, Terry finds a door in the kitchen, which leads to a toilet but when he goes in, part of the toilet falls on his head, landing him in hospital.
The Medfords are about to move house when their daughter Wendy turns up. She announces that she is leaving her husband Roger because he is having an affair with Marjorie, his secretary, though Roger quickly follows and explains that he is merely escorting Marjorie around whilst her husband is abroad and it is all platonic. By the time reconciliation is made the removals man is so annoyed at the family's long-windedness that he starts unloading the van and has to be persuaded by Roger to reload it.
Brian offers to get the Medfords a carpet at a reduced price - in fact it is a cut-off from the new carpet in Terry's office building. However when work colleague Malcolm tells Terry that the office carpet has been stolen Terry assumes that he has innocently fenced it and gets June to help him return it. In the event the Medfords got their carpet legitimately but it is assumed that they were donating it to replace the stolen one.
Despite never having played before Terry agrees to take part in a bridge tournament to impress his boss Sir Dennis and hopes to teach himself in a week. Unfortunately Sir Dennis insists on bringing some friends round for a pre-tournament try out and Terry is forced into various delaying tactics. Finally he bangs his head on the table and claims it has caused him to lose his memory - including how to play bridge.
After seeing graffiti on a wall in the street Terry declares that people should take more responsibility for children and ends up looking after Magnus, Tina's twelve year old nephew, for whom he builds a spaceship for the local fancy dress parade. When Magnus goes down with a rash, Terry 'pilots' the space ship himself but it ends up getting towed away and Magnus's rash is actually red paint as he was the graffiti artist.
After returning a lost budgie June decides she would like pets in the house and agrees to look after animals for friends, including a Yorkshire terrier. Terry accidentally lets the dog out and goes searching for it, ending up in a strange house where he thinks it has gone. After sorting out the mix-up with the angry owners he finds that the dog has gone home without him and eaten his dinner.