Jin Shengjin (Zheng Zaiyong) lost his job due to company restructuring, and at the same time, he was heavily in debt and his wife left him. Jin Shengjin, who was completely disappointed with life, climbed onto the bridge of the Han River and jumped... However, after Jin Shengjin woke up, he found himself drifting to a small island in the middle of the Han River. After a brief attempt to escape failed, Jin Shengjin fell into a Robinson Crusoe situation on the edge of the city. Recalling the cramped and busy modern life, Jin Shengjin gave up the idea of suicide and began to live an alien life relying on various wastes on the island. At the same time, in a high-rise building in the city, an autistic Miss Jin (Zheng Liyuan) happened to witness Jin Shengjin's suicide with a camera. Since then, this girl who only peeked into the street during exercises for a year has entered an alien-like urban Robinson Crusoe in her life. Miss Jin enters the dangerous streets at night to send her signal to Mr. Jin, and Jin Shengjin responds with big words on the beach. This wonderful pair of pen pals slowly maintains this friendship, but in the chaotic city, where will this relationship go?