On a stormy night, three-year-old Nian Nian is abandoned in an alleyway and happens to cross paths with the teenager Lu Ye. Remembering his own past, Lu Ye's heart softens, and he takes her back to his humble rental room. Four teenage boys meticulously care for Nian Nian in clumsy ways, scrimping and saving to hustle for her. During this time, Nian Nian's biological parents demand money, and she faces false accusations from others, while the community also plans to take the child away. At this critical moment, the neighborhood residents sign a joint guarantee, and through their hard work to stand on their own feet, they successfully secure custody of Nian Nian, ushering five mutually reliant souls into a warm and stable new life.