Prim widow Irene Spencer sends a thank you letter to the rather hearty lady,Vera Small, another widow,who did the catering for Irene's daughter Lesley's wedding - where she got rather tipsy. An exchange of letters begins which will be carried on for years,though half of them are rather bitchy. When Vera trips over the dog and falls downstairs Irene sends her flowers but the florist gets the order wrong and Vera moves into her long-suffering friend Audrey's B & B.
Vera has problems with builders whilst Irene is paid court by elderly Romeo Bill Snapes. Vera asks them round for lunch but they get rather too friendly and end up in bed, causing Irene to leave in a huff. Two years go by during which Bill marries a younger woman,Irene's daughter Lesley considers emigrating to Australia and Vera's daughter Karen has an unsuitable relationship. United in irritation the two ladies of letters re-commence their correspondence.
Irene invites Vera to stay and takes her to the Cricket Club dance where she is to present a prize. However,due to a mix-up,Vera is asked to do the honours instead. An aggrieved Irene is put in mind of all the childhood disappointments she has suffered and Vera's attempts to cheer her up go awry. However, Irene has a far bigger problem to worry her, Lesley's imminent departure to Australia, which drives her to drink.
Vera's daughter Karen falls pregnant and Irene visits her. It becomes apparent that Karen gets on better with Irene than she does with her mother, who is unaware that her son Howard is gay. He lives on a farming commune called Sheep-Dippers with his 'friend' Anthony,both of whom are vegetarians but Vera just thinks this is very modern. Irene joins a protest group to stop nuclear waste being dumped under the local golf course.
Irene gets arrested during a demo against the dumping and ends up in hospital suffering from amnesia and prone to bad language. The vicar suggests Vera help her recall who she is by writing to her but the letters are all about Vera. Irene is released but, with her memory restored and finding herself next to a bull-dozer at roadworks,she decides to show her friends what happened at the demo and gets arrested again.
Irene is in jail but popular with her cell-mates by showing them how to get round censorship in letters. Vera writes to her but censors her own letter so much it fails to make any sense. Then Vera gets arrested, following a police raid on the house due to Karen's drug-taking. The two ladies of letters thus end up on the same prison ship preparing the Christmas musical.
Having been considered mad by the court Irene is released from the prison ship 'Pride of Cleveland' and moves into Sheep-Dippers along with Vera's daughter Karen,with her baby Sabrina, and Howard and Anthony. She organizes a Vera Small Is Innocent fork and finger buffet to raise funds to draw attention to her friend's plight. Howard is enthusiastic and misses his mother, Karen believes she should rot in hell
Despite the success of the Free Vrea Small campaign, Vera herself decides she prefers the more exciting life on the prison ship,where she is organizing a performance of 'Les Mis'. Irene, vexed by Howard's whining for his mother and Karen's loose ways, evicts the squatters from Vera's house and moves in. However she learns that the council want to run a new by-pass through the back garden, which is the cue Vera needs to come home.
After getting high on drugs given her by the prison shrink Vera is released and goes to Sheep-Dippers,where she finds her children hard going. Irene sells up and moves into Vera's old house, which she believes to be haunted. She also discovers that the by-pass will probably be coming through the lounge and not the back garden. As the ladies swap pen and paper for emails, Vera records her mixed feelings on the fate of her house - and downs another gin and tonic.
Vera's house gets demolished and, thanks to the credit crunch, once her mortgage has been paid off,she will see precious little of the compulsory purchase compensation. Irene entrusts her to look after her dog, Sidney, who is temporarily lost. Irene is furious but sees a way to patch things up.She has just won a camper van in the Cricket Club raffle and suggests she and Vera -and Sidney - tour the world in it.Vera is dismayed to find the van is old and rather shabby but gets in all the same and the ladies set out on their big adventure.