Intern Lin Xiaoman enters the workplace for the first time, always sticking to her original intention and treating every job seriously. The low-key and diligent cleaning elder by her side has been silently caring for and protecting her. No one knows that this seemingly ordinary cleaner is actually the founder of this office building. A family storm comes suddenly, and events sealed for twenty years are slowly uncovered. He chooses to hide in mediocrity, hiding his identity, and with a father's love as deep as a mountain, accompanies his daughter's steady growth.