MICHELLE MAGORIAN'S best-known book, Goodnight Mister Tom, is one of the few nonfantasy novels for children to have stood out in the past 20 years. Set during the Second World War, it established her as an author concerned with the ways that adults and children can help to solve each other's problems. It has taken her a decade to publish Just Henry, a 703-page doorstopper set in postwar Britain.

Henry is the son of a dead war hero who lives with his mother, his stepfather, their little daughter Molly and his father's mother. Like Will in Goodnight Mister Tom he is friendless and odd, but instead of a mad, cruel religious maniac for a mother he has a bigoted, manipulative and venomous grandmother, who bullies his mother and has Henry hypnotised into believing her stories about his father. Gran teaches him to despise one boy in his class for being illegitimate and another for having a deserter as a father - and what is worse, her prejudices are echoed by many adults in the small seaside town.

Henry thinks he hates reading because his father did, deliberately failing his 11 plus, and resents both his half-sister and his gentle, bookish stepfather. The only bright thing in his life is the cinema, and it is because of his passion for the movies that his enlightened new teacher Mr Finch puts him in a team with the very two boys he despises as illegitimate and cowardly. Their task to research the history of cinema gets them talking to older people, one of them the mildly eccentric, bohemian Mrs Beaumont, who is the good fairy to counter the wicked witch of Henry's Gran.

Little by little, the three boys become friends. Henry's mother, encouraged by Mrs Beaumont, befriends their mothers, gaining confidence in parallel with her son's blossoming personality and friendship with Grace, a dyslexic girl who is continually being punished. Each child discovers an unsuspected talent. Yet it is the camera that Mrs Beaumont lends Henry which leads to the biggest discovery of all - one that will threaten the lives of Henry and his sister, and which could send his mother to prison.

Despite its length (at least 200 pages should have been pruned off) this is a thrilling, richly detailed story that rips along to a hair-raising climax in which Henry and his sister are imprisoned in a cellar and about to be murdered. Several times, I found myself crying; only the greatest authors of children's fiction share this ability to touch the heart.

Just Henry (10+) by Michelle Magorian
Egmont £12.99 Buy the book here

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