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News of "revived people" who should have died humans come back to life was reported all over the world. Meanwhile, Tetsuo Tsuchiya wakes up in the conference room where he works, but his colleague reports that he died of suicide three years ago. However, Tsuchiya, who had a wife and a son and lived a happy life, could not commit suicide, and thought that he was actually killed, lives while pursuing the reason for his death. It depicts how you know the meaning of things, dying, and happiness.