"In the 1970s, box office numbers were going down, with television coming up, so the studios decided to make pictures that would pull in audiences by showing things you couldn't show on the small screen," explains Micha Pletinckx of Marcel, one of the organisers behind the Offscreen Film Festival. A selection of these films is one of the highlights of this year's festival, which runs in Brussels over three weekends in March.

If you haven't seen them, or only caught their echo in the films of western devotees such as Quentin Tarantino, then they are definitely worth checking out. With highly stylised violence, strong female characters and an approach to sex that favours blood and bondage, they have an atmosphere quite unlike anything else. "The filmmakers were usually trying to reproduce manga style, and really going wild with it," Pletinckx says, referring to Japan's long tradition of adult comic books. "The studios allowed them a lot of liberty."

Among the best are the first three Female Convict Scorpion films, directed by Shunya Ito and starring the highly charismatic Meiko Kaji as a woman trying to escape from prison and take revenge on the corrupt police detective who set her up. Visually and thematically, they have an approach to the women-in-prison genre that still feels fresh.

Other sub-genres on show include the girlgang, with Kaji again turning up in Stray Cat Rock: Sex Hunter, with a story that also deals with prejudice against mixedrace Japanese and US military bases in Japan. Then there is organised crime, in films such as Female Yakuza Tale: Inquisition and Torture and Sex & Fury. While the titles need to be taken with a pinch of salt, sometimes they are pretty good descriptions of what you are going to see. Screenings begin at the Nova Cinema, with 35mm prints flown in fresh from Japan, complete with English subtitles.

For those who prefer their exploitation without polish, Offscreen pays tribute to Spanish sleaze master Jess Franco, who will appear in person along with long-time muse Lina Romay. With nearly 200 films to his name, Franco is famous for his female convicts, lesbian vampires and a shaky aesthetic memorably described by one critic as "softcore with a little soft gore".

There's a double bill of Vampyros Lesbos and the English version of Succubus at the Bozar, while Nova offers a weekend that includes Franco's vision of the spy movie in Midnight Party, science fiction in Shining Sex and religious instruction in Love Letters of a Portuguese Nun. You can work out what Ilsa, the Wicked Warden is about without any help from me.

A rather different genre is explored in Offscreen's other main theme this year, the spaghetti western. These emerged in the 1960s when European directors took the Hollywood western, stripped it down to its bare bones, supercharged the violence and let it loose on an unsuspecting world. Eventually Hollywood followed suit, producing its own down-and-dirty westerns in the 1970s.

The genre was pioneered by Italian directors such as Sergio Leone, shooting in Spain with holidaying stars like Clint Eastwood, Lee Van Cleef and Eli Wallach, or locals masquerading under anglicised names. This retrospective includes Leone's classics For A Few Dollars More and The Good, the Bad and the Ugly, plus less celebrated titles like the violently gothic Django Kill... If You Live, Shoot! and the snow-bound The Great Silence. Look out for the faces of Orson Welles, Klaus Kinski, Ringo Starr and even Pier Paolo Pasolini behind the gun smoke.

Offscreen has found the perfect connoisseur to introduce these films, in the shape of British director Alex Cox, who recently wrote a book on the genre. Cinematek is taking advantage of his presence to present a selection of his films, such as the excellent Repo Man and Sid and Nancy, plus the spaghetti-tinged Straight To Hell and Walker. Last year's sequel, Repo Chick, screens at Nova.

For a change of pace, there will be an evening of animation by Bruce Bickford. Best known for the claymation videos he produced for Frank Zappa in the 1970s and 1980s, he is still working and will present a selection of his work on 11 March.

Finally, Offscreen brings us new films such as Hirokazu Kore-Eda's Air Doll, Dominic Murphy's White Lightnin', Jesper Ganslandt's The Ape and Toshiaki Toyoda's The Blood of Rebirth. A few films from Offscreen will also show in Antwerp’s Cinema Zuid.

4-21 March
Across Brussels
www.offscreen.be