College student Youichi Kamisuki possesses a disquieting ability: by gazing into a persons eyes, he can see and relive their past experiences. Leading a stagnant life during a pandemic lockdown, he one day looks into the eyes of a stray cat and instead of a felines memories, he encounters a girl named Misato Yuzuhara, who calls herself Miri. She possesses the complementary power of future sight and can see what lies ahead for those she looks upon. Through the cat, which exists in both their time streams as the stray named Saburo, they realize they are communicating across different eras.

Miri delivers a shocking revelation: a series of murders will soon target Youichis peers, starting with a member of the universitys drama club. She urges him to become a detective to change this grim future. As Youichi investigates, he follows Miris guidance to join the drama club, using her knowledge of future events and her coaching on acting to infiltrate the group and prevent the killings. The story takes place against the backdrop of a society adapting to pandemic isolation, with online classes and remote activities like Zoom rehearsals becoming key elements of the mystery.

As their bond deepens, Youichi becomes determined to meet Miri in person. However, her presence in the past carries a devastating truth. She hints that in Youichis present, she no longer exists, saying, In your time, I am already. The narrative weaves together the investigation into the drama club serial murders, the mystery of a letter from the dead, and the central question of whether their love can transcend the barrier of time that separates them. Youichi must unravel the lies and truths in Miris words to solve the case and understand who she truly is.