When April, a Filipino migrant worker, returns home with the ailing Taiwanese grandpa she cares for, while the grandpa's recently released son comes home only to find the house empty.

Zhang who has never had any work experience, came to work in a tall building to help with family expenses. He encountered various strange scenes, both among colleagues and between the boss and employees. Zhang seemed to gradually integrate into this environment, until his sister suddenly appeared in a panic. This building seemed unusual, and the two tried to escape from the structure.