At 70, Meng Yayun, suffering from dementia, refuses to become a burden on her family and runs away from home. By mistake, she boards a time-travel bus and returns to the age of 20. Under the assumed name Xiaoyu, she enters the entertainment industry, where she unexpectedly meets the CEO Gu Yunhai, who looks just like her former lover. After an authentic performance in a period drama unexpectedly makes her famous, she secretly helps her grandson, Lin Xiaochen, pursue his dream of entering show business. Meanwhile, she and Gu Yunhai finally resolve the emotional regrets that have lingered for 50 years. When her grandson suddenly develops a serious illness and needs a close family member to save him, she resolutely sacrifices her youth to restore his life, returning to her elderly form. In the end, her son, who had recognized her long ago, encourages her to live for herself. Making peace with her past, she reunites with her family and finally finds redemption and happiness in her later years.