Mr. Arthur Radley (Boo)
Who is Boo Radley?
Who is Boo Radley to others?
Towards the end of the novel, when Jem and Scout are attacked, Boo helps them proving to everyone that he isn't who they think he is.
"Every move he made was uncertain, as if he were not sure his hands and feet could not make proper contact with the things he touched." first paragraph, page 235, chapter 31
These pieces of evidence show how Scout and Jem feel about Boo at the beginning of the novel.