So much talent in the service of pain

Just before America entered the war in 1941 Nelson Rockefeller invited two master film-makers to the Museum of Modern Art in New York to view Leni Riefenstahl's 1934 documentary, Triumph of the Will. The millionaire philanthropist wanted to know if Riefenstahl's obvious support in the film for the Nazis could be turned on its head and through editing be transformed into an anti-Nazi polemic. The Surrealist film-maker Luis Bunuel said the film's spell- binding, processional shots of fluttering flags and swastikas, stamping boots and adoring up-and-under shots of Nazi leaders could not be altered. After Charlie Chaplin came to MOMA a week later, Rockefeller asked the projectionist what the silent comic's reaction had been. Chaplin, apparently, laughed throughout.

These two reactions have framed the debate over Leni Riefenstahl's work: a wary appreciation of cinematic skills devoted to an inappropriate subject, and ridicule for a bombastic style devoted to messianic orators such as Hitler and Josef Goebbels.

But in the first English language biography of Riefenstahl, Steven Bach ventures further to insist that Riefenstahl's skills lent credibility to a horrific regime and that she is therefore morally culpable, if not for the actions of the Nazis, then at least in part for their visceral appeal.

Bach certainly makes the case that Riefenstahl was a sharp- elbowed operator who held a perpetual belief in her own charms and artistic vision. She left a trawl of bruised lovers - some Jewish, later to be disclaimed - in her wake as she clawed up the production ladder as a star of "Alpine" films - a romantic sub-genre that held little appeal outside Germany. By 1933, Reifenstahl's career had stalled and, though she had co-directed one of her mountain melodramas, she was desperately in need of a film subject to maintain her star status. Fortunately for her, she then met Adolf Hitler.

"Once we come to power," he suggested, "you must make my films." She said she couldn't join the Party because "you have racial prejudices." Yet, far from antagonising the would-be dictator, her reply provoked an amorous attack. But the leader noted her coolness and pleaded, "How can I love a woman until I have completed my task?" Hitler's press agent, Ernst Hanfstaengl, who observed one of these romantic interludes between the two, remarked that actually "Leni was giving him the works, a real summer sale of feminine charms" and, if Leni couldn't "manage this, no one can." But Hitler was asexual, as Hanfstaengl suspected, so he wasn't surprised that Leni's advances only threw the Fohrer "into a panic".

Despite his romantic qualms, Hitler retained a belief in Riefenstahl's cinematic ideas and within a month of becoming Chancellor in January, 1933 he personally gave her the surprising commission of filming the vast Nazi Rally which would take place in Nuremberg the following June. That film, in fact, was a try-out for the next year's rally, which would be filmed under the title of Triumph of the Will. Bach drives home that Riefenstahl knew exactly what was expected of her and her documentary from the new government. In her own words: "The bond between the Fohrer and the people was of supreme importance. Showing it, expressing it, is one of the tasks I have set myself." In the opinion of Goebbels the film achieved its exact purpose. "It documents the transition of the Party into a State."

Bach, who has written several outstanding studies of Hollywood, expertly explains the cinematic technique which underlies Triumph of the Will's power to entrance. Riefenstahl's flair, he notes, "for visual moods and motifs, for dynamic compositions, for rhythmic counter-points of picture and sound" transformed "images into myth and aestheticised [Nazi] power".

Riefenstahl went on, again at Hitler's behest, to film Olympia, her recording of the 1936 Berlin Olympics. Less overtly political and more poetic in tone the documentary aggrandises Aryan beauty. But it also features the now famous footage of the black American athlete Jesse Owens repeatedly winning gold medals to the consternation of Hitler. Yet, despite its acclamation and gala premieres throughout the world, the film marked the apex of its maker's career and, though she continued to be financed by Goebbel's Propaganda Ministry, Riefenstahl never made another film.

From then onwards and up until her death in 2003, Riefenstahl denied that she had cast a sheen of artistic glamour over the Nazis and became one of the many Germans who insisted they "didn't know what happened" during the war. Bach more than makes the case that she did know. He places her at a Wehrmacht massacre of Jews in Poland during the fourth week of the war and produces evidence that she used gypsies as unpaid, forced labour for one of her unfinished films.

Lucidly written and thoroughly researched, Bach's biography is magisterial with every lie and obfuscation that Riefenstahl resorted to nailed down and rebutted. But the author commits one sin of omission. Why, over the past 60 years has his subject been singled out for quite so much attention?