Room, By Emma Donoghue

Jack is a five-year-old boy. Since birth, he has been trapped with his "Ma" inside an 11ft-by-11ft cell.

They have only a TV, a bed, a stove and a few tattered toys. Jack hides when their captor visits at night. To make the internment tolerable, Ma has constructed an elaborate fiction: that everything they witness on TV is a fantasy. There is no outside; the only reality lies within the room.

Emma Donoghue's Booker-shortlisted novel was inspired by the true story of Elisabeth Fritzl, who was imprisoned in her father's basement for 24 years. To use such material as the basis for imaginative writing is audacious, but Donoghue succeeds beautifully. Neither prurient nor sensationalist, her novel transfigures this darkest of stories into a revelatory, even life-affirming work of art.

The story is told from Jack's credulous perspective. Eventually, he and his Ma effect an escape. At this point the book threatens to become a heavy-handed satire of the frenzied media interest in the Fritzl case: Ma's lawyer encourages her to sell her story ("The whole living-on-less thing, it couldn't be more zeitgeisty") and she agrees to a TV interview in which she is asked a series of predictably impertinent questions.

But Donoghue's narrative soon recovers its former subtlety. Her account of Jack's adjustment to his new surroundings is exquisitely observed, and a fittingly bittersweet conclusion to a unique novel.