At first it’s not immediately clear what “Amen” says about contemporary culture. The play and film are based on the true account of Kurt Gerstein, a devout Protestant and Waffen SS chemist who supplied the Nazis with the toxic gas Zyclon B. Unbeknownst to Gerstein, the gas was used to exterminate Jews in concentration camps. When he finally learned its true purpose, he was so horror-stricken that he enlisted the help of a young Jesuit priest with family ties to the Vatican to plead with anyone who would listen–fellow Germans, the Allies, the Roman Catholic Church and eventually the pope–to denounce the slaughter. No one did. (Gerstein was eventually captured by the French; while in prison, he wrote about the atrocities he saw in the camps, and his report was later used as evidence against the Nazis in the Nuremberg trials.) Though “Amen” is about events that occurred during World War II, Costa-Gavras maintains that its primary subject–indifference–still plagues society today. “Indifference did not start with the camps nor did it end with the war,” he says. “Look at the indifference with which we are letting the African continent die. Our passivity is a crime in itself.”

Costa-Gavras became fascinated with the subject when he saw “The Representative” onstage during its first run in Berlin in 1963. That production sparked plenty of controversy of its own; radical Catholics protested outside the theater and threatened the cast. One night an audience member leaped onstage and socked the pope character in the face, leaving the actor bleeding. At that time Hollywood titan Sam Spiegel planned to make a screen version of the play–but only if Pope Paul VI would give the project his blessing. The pope refused, and the picture never got made.

All along, Costa-Gavras harbored his own dreams of turning “The Representative” into a movie. When the rights finally became available four years ago, he teamed up with French producer Claude Berri and began his research and writing. He expanded the play into an epic that spans the continent, from the desolate camps Belzec and Treblinka to the opulent corridors of the Vatican. Though Costa-Gavras–who now lives in Paris–filmed “Amen” in English, he hired German actors to play Gerstein and his Mephisto-like superior, and a French Jew–Mathieu Kassovitz, most recently the heart-stopping crush in “Amelie”–to portray the young Italian priest. “Mathieu was apprehensive,” Costa-Gavras admits. “But once he put on the priest’s robes, his posture and sense of himself changed. He became the priest.”

Unlike Steven Spielberg in “Schindler’s List” and Roberto Benigni in “Life Is Beautiful,” Costa-Gavras chose not to show the suffering in the camps. “Their reality is beyond the reach of film,” he says. Instead, he captures the reaction of observers to the slaughter, some proud of its efficiency, others–in particular Gerstein–tormented by what they witness. The effect is profoundly disturbing. After Costa-Gavras presented the film at the Berlin Film Festival in February, the audience remained silent for a full minute before erupting into applause.

Costa-Gavras hopes his film will help spur change within the Catholic Church. When “The Representative” first opened and scrutinized the church’s role during the Holocaust, the Vatican made public some of its archives from World War II that implicated its role in wartime politics. In recent years, journalists and authors have dissected the subject in newspapers and best-selling books, prompting Pope John Paul II to refer to the Holocaust in a 1999 speech and ask for forgiveness for the “historic mistakes” the Catholic Church has made. Costa-Gavras hopes that “Amen” will push the Vatican to open the rest of its archives from that period. “If a film on such an important subject as the Holocaust can raise questions for the public to discuss–questions that could change the way things are done or perceived–then it has achieved something substantial,” he says. Amen.