The film is based on Hong Ying's "Shanghai Death" and Yokomitsu Ryuichi's "Shanghai". In 1941, the famous actress Yu Jin returned to Shanghai during the isolated island period, ostensibly to perform in the play "Saturday Novel" directed by her old love. But what is her real purpose? To rescue her ex-husband? To collect intelligence for the Allies? To work for her adoptive father? Or to escape the war with her lover? What is her real mission? As she embarks on her mission, it becomes increasingly difficult to distinguish between the enemy and us. The fate of a woman is closely tied to the times. How can she make a choice that changes the world? In and out of the play, who can escape?