In March 2018, when Huang Xiaodi turned 17, her family told her to return home to Jiangyin, in eastern China’s Jiangsu province, so they could throw a birthday party for her. But before she had a chance to cut the cake, Huang was ushered to a car with her father, sister and brother-in-law. “They said they wanted to take me shopping,” Huang recalls of the evening. “I was surprised, thinking, ‘Shopping? At this hour?'” It was about 20 minutes into the drive that Huang realised something was wrong when the car turned onto a highway and headed out of the province. “Where are you taking me?” she asked. “We’re going to cure your illness,” replied her father. Hours later, Huang would begin to understand when a round but sturdy, 40-ish drill-instructor type wearing camouflage gear and with a buzz cut appeared to greet them. “What is this place?” she protested. “Who is that man?” “He can cure you,” her sister replied. Then she and their father took hold of Huang’s arms and pulled her from the vehicle, dragging her past a set of iron gates towards the man she would soon come to know, and dread, as Old Zhang.