Yang Shi-nan is a 14-year-old boy. During class one day, he finds his stomach hurting badly. He rushes to the toilet and notices his urine becoming blood-red.
After seeing a doctor, he is diagnosed with “disorders of sex development,” commonly known as intersex. Shi-nan’s parents decide to accept “sex reassignment surgery”, turning Shi-nan into a female. After the surgery, her parents change her name to Yang Shi-lan, and they move to a new city to start a new life.
The butterfly is about to break out of its chrysalis. Can Yang Shi-lan/Yang Shi-nan truly embrace her/his transformation?