The Jiang family of the capital welcomes back their biological daughter, Jiang Nanxing. She saves up money to help her bullied adoptive younger sister, but when her black card has no spending authorization, she cannot withdraw a single cent. With no other choice, she hauls cement and survives on leftovers. When her older brother discovers the truth, the whole family learns how hard Jiang Nanxing has worked to protect her sister. She stands up to bullies and exposes the Zhao family's scam, only to discover that her father's death holds another secret. An old silver lock reveals the story of Zhou Xiulan, who disappeared many years ago, and an old service station. Gradually, Jiang Nanxing realizes that being fiercely protective means more than protecting one's family; it also means standing up for people who are bullied and exploited. She reopens the Xinghuo Service Station, remaining sharp-tongued and proud, but turning her determination to protect others into a spark that lights up the lives of ordinary people.