Fukurō no Shiro (1963)

Fukurō no Shiro (梟の城, Owls' Castle) is a 1959 ninja-themed novel by the debuting Japanese author Ryōtarō Shiba, which won him the Naoki Prize in 1960 after the story was published by Kodansha. It was later made into two jidaigeki-genre films, Castle of Owls in 1963 and Owls' Castle in 1999.

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