Frank Riley's life turns upside down when his son, Brian, walks back in to his life. Not only is he looking for a job and a place to stay, he also seems to be bringing his God-fearing attitude to bear on Frank's less than saintly lifestyle.
Brian spends his first Sunday in his new, sinful surroundings. A chance encounter with Polly Pickles, a 75 year old who has a lifestyle alien to him, makes him see his father in a new light.
It's the night of the Lancastrian Insurance annual staff dance and, once more, Frank is about to give George Pollitt his comeuppance.
Having been confined to bed in a private room at St. Mary's hospital, Frank finds himself under the disapproving care of Sister Esmerelda. Not only is she shocked by his unmentionable complaint but by his ignorance as well.
Frank has managed to dispatch Brian on a works' outing and so has Saturday afternoon free to frolic with Ethel. That is until Brian's uncle Islwyn decides to pay a visit from Wales and Frank finds that it is not just the railways that have a Saturdays Excepted policy!
Brian succeeds in getting the flat to himself when he persuades Frank to go out, but his evening with his sweetheart, Janice, is soon interrupted.
It's time for Frank to pull his socks up at work - at least that was the advice given to him by Jeremy Spear, an inspector from head office. However, work and night are normally mutually exclusive for Frank!