In Wonder by R. J. Palacio, Jack makes a huge mistake on Halloween. The whole class is in costume, and he doesn't realize that August has switched costumes at the last moment and is sitting close by. Julian is insulting August as usual and wondering why Jack is friends with him. Jack says he only is because Mr. Tushman asked him to "hang out" with August and now August always follows him around.

August is horribly hurt, and he doesn't want to go to school any more. He pretends to be sick and goes home with his mom, but he never tells his parents the real reason for his "illness." August is sick at heart. He thought Jack was his best friend.

August does confide in his sister, Via, however. She tries to reassure her brother that Jack didn't really mean what he said. She doesn't really convince August, but she does manage to get him to go to the Halloween parade with her.

August also tells his friend, Summer, what happened with Jack, but he swears her to secrecy. Jack doesn't understand why August is mad at him, and he asks Summer. She will not tell him anything except "Bleeding Scream." Jack realizes that he saw someone in that costume on Halloween and that it was August. He understands now that August heard everything he said, and he is horrified. He apologizes to August, and the two renew their friendship.

Via, however, isn't quite as ready to forgive Jack as August is. Jack goes over to August's house to work on their science-fair project, and August introduces Jack to Via. Jack notices that Via looks at him carefully, and he realizes that August must have told her what happened at Halloween. Via says nothing about the incident, however, but when she leaves the room Jack asks August if he told her about Halloween and if she hates him. August replies, "Both."