Sophie Hatter is the central protagonist of Diana Wynne Jones’s fantasy novel Howl’s Moving Castle. The novel was first published in 1986 and follows Sophie after the Witch of the Waste transforms her into an old woman.
Sophie leaves her family’s hat shop and finds refuge in the moving castle belonging to the wizard Howl. Inside, she encounters Howl, his apprentice Michael, and the fire demon Calcifer. Her practical personality and willingness to challenge magical rules drive much of the story.
The novel’s magic treats expectations and self-belief as important forces. Sophie initially assumes that, as the eldest of three sisters, she is destined to fail, but her actions repeatedly contradict that belief. Hayao Miyazaki’s 2004 animated film shares the title and several characters but changes major plot details, so the book and film should not be treated as identical versions of the story.