"The Treasure of Lemon Brown" is a story about Greg Ridley, who starts off having a bad day. Because he is doing poorly in school, his father banishes Greg to his room to study. Greg decides to leave the house and goes to an abandoned warehouse, where he meets Lemon Brown. Through his interactions with Lemon, Greg begins to reflect on his life.
Greg is very angry at his dad because he's been grounded from playing basketball - his passion. Greg runs away, but after meeting Lemon, he rethinks his anger. His dad only wants the best for him.
Lemon's sister raised his son while he traveled and played his music. He learned that his son was killed in the war and that he had kept his dad's harmonica and news clippings with him.