Takekuni Kitayama (born 1979) is a Japanese mystery writer from Morioka, Iwate Prefecture. He made his literary debut in 2002 after winning the 24th Mephisto Prize for "‘Clock-jō’ Satsujin Jiken." Known for combining large-scale physical tricks involving buildings and mechanical devices with fantastical settings such as doomed worlds and strange castles, he has written numerous works of honkaku mystery, including his Castle series. His representative novel, "‘Clock-jō’ Satsujin Jiken," is set in a castle equipped with three enormous clocks as the end of humanity approaches, where a succession of headless bodies leads to a mystery built around the architecture of the castle itself.
