Goodnight Mister Tom follows the story of 8 year old evacuee William Beech who is sent to live in the heart of the English countryside in the quiet village of Little Weirwold during the Second World War.
William arrives in the village physically and emotionally scarred by the cruelty of his mother. After her insistence that William should live in a religious home, he is sent to live with Tom Oakley, an elderly recluse.
Although initially scared of this new world, William is gently nursed back to full health by the kind and compassionate Tom. William begins to trust Tom and starts to enjoy his new life in Little Weirwold, making friends with Zach, a fellow evacuee, and local children George, Carrie, and Ginnie. Although he starts school illiterate, Tom and his teacher Annie Hartridge help William read and write by using his natural gift for drawing and painting. Soon William catches up with his new found friends and starts excelling in class.
As William is changed by Tom’s generosity and teaching, Tom is also changed by William. He discovers that Tom’s life has been filled with tragedy. Forty years ago his wife Rachel died giving birth to their daughter Jenny. Since then Tom has a lead a reclusive life, living alone apart from the company of his dog, Sammy. Tom loves William’s artistic talent and as the pair grow closer, Tom gives William Rachel’s old paints and brushes from the attic. William’s place in the house has revitalised Tom’s life and he is surprised by how nice it is to have some company again.
This new found stability is upset when William’s mother suddenly demands his return to London, claiming she is ill and in need of William to look after her. William has mixed emotions about going back; he loves his new home but also feels that the lessons he has learnt could help him and his mother. Unknown to William she has had a new baby, to whom she is brutally cruel. During a horrific reunion she hits William.
Three weeks and four days later, Tom begins to get worried because William hasn’t returned any of his letters. Determined to discover why, Tom travels to London with Sammy in search of William. After knocking on William’s door and with no answer, a worried Tom convinces a local policeman to break the door down. On entering the house Sammy sniffs out William and the now dead baby who have both been locked in a cupboard.
Whilst William recovers in hospital the doctors advise Tom that William should be put into care. However, Tom thinks that William would be better off with him in the countryside so Tom sneaks William out of the hospital and takes him back to Little Weirwold. After a period of recuperation, William eventually starts to become happy again.
The authorities visit Mister Tom in Little Weirwold to inform him of the suicide of William’s mother. They say that William should be sent to a special home, but the local doctor suggests that William should be adopted by Tom. William agrees. This comes as a great relief and comfort to William who finally has a father and the start of a real family.
Final tragedy comes as William’s friend Zach is killed in an air raid during a return visit to London. William is very sad but with the help of Ginnie, George, Carrie, his old teacher Annie Hartridge and her new baby, William settles into a new, happy life with his father, Mister Tom.