At 69, Lin Wanxiu accidentally discovers that someone else had impersonated her identity in the college entrance examination years ago. Carrying the regrets of her past, she returns to the 1977 examination hall, determined to protect her admission letter and uncover the secrets between her fiancé, Zhou Jianguo, and Sun Meihua, a sent-down youth. Facing one test after another, she secretly gathers evidence. With the help of teachers, friends, and the police, she uncovers the truth, enters medical school once again, and passes on the courage to change one's destiny to more girls.