The film focuses on an aging society and tells the story of the nanny assassin Ye Xiaolin (played by Wan Qi), who disguises herself to enter an elderly family to carry out a murder. During this time, her encounter with the zookeeper Ma Deyong (played by Rao Xiaozhi) disrupts the balance of her original life, and their fates intertwine and change. Through exploring issues such as the dignity of the elderly, family relationships, and death education, the film evokes the audience's attention and reflection on the questions of life and death.