The novel tells of a 43-year-old man who dies and wakes up back in 1963 in his 18-year-old body. He relives his life with all his memories of the previous 25 years intact. This happens repeatedly, with the man playing out his life differently in each cycle. The novel was a bestseller in Japan. Its time-loop concept has been referenced as a precursor of Harold Ramis' comedy-drama "Groundhog Day" (1993). Richard A. Lupoff explored a similar premise in his 1973 short story "".