Nine-year old Zi Jun lost his father when he was young and led a lonely life with his mother. He was extremely shy and very dependent on his mother. "You are already nine, why are you so timid?" His mother was always encouraging him to be more courageous. Then, his mother's decision to move to a new place brought about an enormous change to his life. Since then, Zi Jun began to lead a restless and anxious life.
His new home was situated above a hamburger shop on the street leading to his school. Zi Jun, who loved to eat hamburgers, was happy to live above the most popular hamburger shop on the street. But then, the dirty and old surroundings of the street, the squeaky stairway, the fierce landlady- Auntie Mary, the bullying housemates and the old eerie tree outside his bedroom window; all made Zi Jun's life very miserable and he was always in fear.
Luckily, the landlady's daughter, Xiao Qiao, was warm and cheerful which made his life staying above the hamburger shop more bearable. Every time Zi Jun has a problem, she would come out and protect him. Zi Jun was very grateful to Xiao Qiao and at the same time admired her courage, hoping to be like her one day, not to be afraid of anything anymore. But, will the coward become a hero?