sentences:  The Gray Prince
  
  The Gray Prince is a science fiction novel by American writer Jack Vance, first published in two parts in "Amazing Science Fiction" magazine (August and October 1974 issues) with the title "The Domains of Koryphon".Given that the novel's setting, the planet Koryphon, is integral to the plot, "The Gray Prince" may be said to belong to the science fiction subgenre of the planetary romance.