IT'S GOING to be a tough sell to get people to see 1) a Polish film that 2) is about the methodical, psychological brutalization of a female prisoner and which 3) never lets up for two hours. But "Interrogation," which won the 1990 Cannes Best Actress prize for Krystyna Janda, is all of these things and more.

Set in Poland's totalitarian 1950s, which by enormous implication mirrors Jaruzelski's Poland of the 1980s, Ryszard Bugajski's film stays right under your skin. There's a knowing chilliness about the whole production. You know director Bugajski didn't make too much of this up; you know the performers didn't need too much instruction about Gestapo-state life.

Janda plays a fun-loving cabaret performer who, after a show, is invited for a drink by ostensible admirers. After they get her completely bombed, the men (actually security police) spirit her away to jail. She awakens to find herself a political prisoner, faced with the allegorically named Citizen Major (Janusz Gajos), who asks her to "start at the beginning, like a confession."

Asked about her sexual history, and her personal connections with a certain Col. Olcha, a man suspected of espionage, Janda realizes she's a pawn in a greater "investigation." She also realizes her denials are falling on obstinately unbelieving ears. Starved, confined, under constant physical and psychological torture, with confessions constantly thrust under her nose, Janda undergoes an excruciating test of inner strength, but she never gives up her spirit.

This is a sensational performance by Janda, an increasingly riveting tour de force. The other actors, including Agnieszka Holland as a Communist-sympathizing prisoner, have similar effect. As the Major, Gajos is a collection of blue-suited, authoritarian gestures: the meticulous way he arranges his pencils, the disgust with which he wipes his hands after pulling Janda's hair violently, his intermixing of sweet tones and cruelty. As Janda's second interrogator, who becomes sympathetic to, then infatuated with her, Adam Ferency is memorably empathetic.

"Interrogation," which Bugajski completed in 1982 (smack-dab in the middle of martial law), was banned immediately, but the director escaped to Canada with an illegal video copy and had it shown at various festivals. His efforts to have his work shown prove to be worth all the trouble. This may be harrowing subject matter, but it's vital viewing.

INTERROGATION (Unrated) -- In Polish with subtitles. Biograph.