Fukurà  no Shiro (æ¢Âã®åÂÂ, Owls' Castle) is the ninja-themed 1959 debut novel of Japanese author Ryà Âtarà  Shiba, which won him the Naoki Prize in 1960 after the story was published by Kodansha. It has been adapted into a 3-part "Naoki Award Series" TV broadcast on the Fuji Television Network in 1960, and into two jidaigeki-genre films, Castle of Owls in 1963 and Owls' Castle in 1999.
, literally "Owls' Castle Ninja Secret Handbook", also known as Samurai Spies (not to be confused with the unrelated film Samurai Spy), is a 1963 Japanese adaptation directed by Eiichi Kudà Â. It starred Ryà «tarà  à Âtomo in the lead role.
is a 1999 Japanese adaptation directed by Masahiro Shinoda starring Kiichi Nakai.