Castle Orgies (1971)

Castle Orgies (1971), also known by its original Japanese title Irogoyomi Ooku hiwa, is a Japanese historical drama directed by Isao Hayashi and produced by Nikkatsu. Set in the Tokugawa shogunate's inner court, the film follows a young woman drawn into the highly controlled world of the shogun's harem while her relationship with a samurai is placed under severe pressure. Running approximately 68 minutes, it combines period melodrama with the erotic-film conventions of early 1970s Japanese cinema.

The film is notable as one of the first entries in Nikkatsu's Roman Porno series and as the opening installment of the studio's nine-film Eros Schedule Book cycle. Its period setting distinguishes it from the contemporary urban stories that accompanied Nikkatsu's launch of Roman Porno, while its tightly structured format reflects the commercial and stylistic conventions the studio was developing at the time.

• Released theatrically in Japan on November 20, 1971, on a double bill with Apartment Wife: Affair in the Afternoon.
• Directed by Isao Hayashi, with a screenplay credited to Jirō Niizeki and cinematography by Kenji Hagiwara.
• Setsuko Ogawa made her film debut as the leading performer; she subsequently became associated with Nikkatsu's historical erotic dramas.
• The film was the first of the nine-film Eros Schedule Book series.
• A 2001 all-region DVD release from Tai Seng included Chinese and English subtitles; the film has also received later repertory screenings, including a 2026 presentation at the Cinémathèque Française.