It was February 2012, on a crowded Spring Festival train traveling from Guangzhou to Dazhou, Sichuan. A green passenger train was packed with travelers. A railway police officer walked through one overcrowded carriage after another, keeping watch over the passengers. During the patrol, the officer crossed paths with a young woman. Then, the crowded carriages gradually became empty. The train picked up speed. No one knew where it was truly headed.
