Compare Boo's representation early in the novel to how he is seen at the end of the novel.

Boo Radley

A recluse who never emerges from his house. As a young boy, he was in trouble with the police, and his strictly religious and reclusive parents have kept him indoors ever since. A prisoner in his home, he stabbed his father with scissors once, and no one has seen him since. The town has developed a myth that he is an insane monster who wanders around at night peering into people's windows. Throughout the book, he lives with his brother, who is highly controlling.

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Throughout the novel a different Boo emerges; he can be playful giving, and protective, and yet remain a recluse. He saves Scout and Jem, and is in essence the story's hero.