A 40 year old poet running simultaneously to fat and seed suddenly finds himself in the body of his 19 self. The immediate advantage is that he can seduce any woman he comes across, without trying, and sometimes even against his will, So Jurgen, the eponymous hero of the novel by James Branch Cabell is both driven and chased on a knight's quest through a variety of mythological worlds including versions of Heaven and Hell, until he becomes disenchanted with his enchanted existence and gratefully seizes to the opportunity to return to his natural body and his shrewish wife.
First published in 1919, Jurgen was a hit of the jazz age, its popularity boosted by a prosecution by the New York Society For The Prevention Of Vice. Its reputation popped with the stock market bubble and when James Branch Cabell died in 1958 both he and his masterpiece were long forgotten.