Fukurō no Shiro is a 1959 ninja

Ninja

A or was a covert agent or mercenary of feudal Japan specializing in unorthodox arts of war. The functions of the ninja included espionage, sabotage, infiltration, and assassination, as well as open combat in certain situations...

-themed novel

Novel

A novel is a book of long narrative in literary prose. The genre has historical roots both in the fields of the medieval and early modern romance and in the tradition of the novella. The latter supplied the present generic term in the late 18th century....

 by the debuting Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

ese author Ryōtarō Shiba

Ryotaro Shiba

, born in Osaka, Japan, was a Japanese author best known for his novels about historical events in Japan and on the Northeast Asian sub-continent, as well as his historical and cultural essays pertaining to Japan and its relationship to the rest of the world....

, which won him the Naoki Prize

Naoki Prize

The Naoki Prize is a Japanese literary award presented semiannually. The official name is Naoki Sanjugo Prize. It was created in 1935 by Kikuchi Kan, then editor of the Bungeishunjū magazine, and named in memory of novelist Naoki Sanjugo...

 in 1960 after the story was published by Kodansha

Kodansha

, the largest Japanese publisher, produces the manga magazines Nakayoshi, Afternoon, Evening, and Weekly Shonen Magazine, as well as more literary magazines such as Gunzō, Shūkan Gendai, and the Japanese dictionary Nihongo Daijiten. The company has its headquarters in Bunkyō, Tokyo...

. It was later made into two jidaigeki

Jidaigeki

is a genre of film, television, and theatre in Japan. The name means "period drama" and is usually the Edo period of Japanese history, from 1603 to 1868. Some, however, are set much earlier—Portrait of Hell, for example, is set during the late Heian period—and the early Meiji era is also a popular...

-genre films, Castle of Owls in 1963 and Owls' Castle

Owls' Castle

Owl's Castle is a 1999 Japanese ninja-themed film written by Masahiro Shinoda and Katsuo Naruse and directed by Masahiro Shinoda. It is a remake of the 1963 film Castle of Owls, based on Ryotaro Shiba's 1959 novel under the same name.The film starred Kiichi Nakai, Takaya Kamikawa, Mayu Tsuruta and...

in 1999.

Castle of Owls

Castle of Owls (忍者秘帖 梟の城, Ninja Hicho Fukurō no Shiro; literally: "Owls' Castle Ninja Secret Handbook"), also known as Samurai Spies (not to be confused with the unrelated film Samurai Spy

Samurai Spy

is a 1965 film directed by Masahiro Shinoda, based on a novel by Koji Nakada. Made during the height of the cold war, the film follows the lives of spies caught up in the power struggles of their times.- Story :...

), is a 1963 film directed by Eiichi Kudō. It starred Ryūtarō Ōtomo

Ryutaro Otomo

was a Japanese film actor. He committed suicide in 1985.- Filmography :He played in 272 films:* * Akō Rōshi * The Magic Serpent - External links :...

(as Juzo), Minoru Ohki (as Gohei), Hizuru Takachiho (as Kohagi), Chiyoko Honma (as Kizaru) and Choichiro Kawarazaki (as Kumotaro) in the main roles. The film is much less known than its remake.