The story is about a boy named Greg who meets an old man named Lemon Brown in an abandoned building. Some thugs try to steal Lemon Brown's famous treasure but he would rather die than give it up. Greg and Lemon Brown scare off the thugs with noise. Lemon Brown's treasure turns out to be a harmonica and newspaper clippings of his son who died in war, which was very important to him as his only memory of his son.