Troublemaker and Guoli play basketball in school during the holidays. Bored, they draw graffiti on the walls. The janitor uses a mobile phone to photograph them in action. When Wu Yanbin reports for work, he finds that the school principal is his former colleague, Cui Dabao. He tells Dabao that Siman is studying overseas and that he had returned home first. The janitor shows Daoqiang the photos. Troublemaker declares he did everything by ...