When Yu Huainan was 19 years old, he met a boy in black wearing a violin by chance, which led to a ten-year abstinence entanglement. When the lights went out, Yu Huainan returned to being a teenager. She wanted to change the future, but accidentally entered the entertainment industry and met the popular idol Zhou Xinsheng. In and out of dreams, which one is true and which one is false? How should Huainan choose? From sweet and ignorant to tenacious and decisive, how does Yu Huainan continue his triple life...