"5 cops only in Sham Shui Po tonight!" PC46700 said. In the deep of the night, a police officer was dispatched to an old building where he found a Vietnamese drug addict in a partitioned room. His investigation was inexplicably filmed by a would-be documentarian, which led to a conversation with the police constable recollecting his early days and involvement with the Vietnamese refugees more than twenty years ago. An apparently unrelated group of people had this unexpected encounter when the majority of the police force gathered at Mongkok during the Umbrella Movement.

Li Jan, a girl from Northern China travels to Hong Kong with a 90-Day tourist visa to meet with a group Tat, to be brought into the world of underground prostitution. On this first night, she is guided through different back alleys into a series of red light motels, while trying to make a single phone call. As she delves deeper into the world, the phone call seems beyond her grasp.