The general public thinks of 1993 fact-fiction Schindler’s List as Holocaust touchstone. That, however, is because of the rarity of showings of Claude Lanzmann’s 1985 Shoah, which includes a four-hour-thirty-three-minute first part and four-hour-fifty-one-minute second (both titled “eras”).

Even with a one-hour intermission at a Museum of Modern Art showing, the 564 minutes definitely test audience stamina. Its spoken text simultaneously published by the director and associate Simone de Beauvoir, the unique documentary employs neither music, historical footage nor re-creations. Recurring interviewees and images thread together related subjects. Emphatic among the latter visual glue are iron rails, rural stations, ominous freight cars and locomotives whose black smoke parallels that which bellowed from crematoria chimneys that today overlook peaceful woods, fields and monuments.

Lesser known facts emerge -- the brutal participation of Ukrainian troops; trains carrying Jews to doom were booked through a state tourist agency at so much per distance and capacity and, confirmed with other nations through which they passed, included Pullmans for the wealthier as well as the infamous boxcars. Noam Chomsky observed the seductive power of statistics to push aside outrage at evil, but interviews with Nazi officials are outrageous precisely on account of the matter-of-fact discussions of logistics, in one case a lecturer’s pointer being used to indicate gas chamber location and procedure.

In the present of 1985, the film peels aside protective mental scar tissue, bringing speakers back to the suppressed. Among them, three strong men crumble and scarcely can continue: Israeli barber Abraham Bomba describes shearing hair (for shipment to the Reich) in Treblinka’s “undressing room” beside the chambers, talking as from a distance until reaching a fellow barber’s encountering his wife and daughter there; Filip Müller on his “special detail” work in the chambers and oven rooms; and an elegant U.S. professor who was then a courier for Poland’s government in exile and, for first-hand knowledge, twice entered the dying Warsaw Ghetto.

There are too many others to enumerate, like 1943 Ghetto uprising fighters, extermination camp revolt planners (New York City’s Rudolf Vrba), railroad driver-engineers and station masters, survivors now returned to Corfu or transplanted to Cincinnati. The first “era” concentrates on Poland and its notorious camps and, indeed, opens with Simon Srebnik on the same Narew River singing the same German song that, as a child, troops had forced on him; the middle-aged Chelmno survivor returns, to stand bemused among neighbors who soon say nasty things on the steps of the Catholic church where Jewish neighbors were penned to await the gas vans.

Peasants, villagers and farmers seem unbothered today about what happened then, when they plowed in earshot of screams, as they gossip of Jewish “gold” and greed and the beauty of their women -- local ladies admit relief such sexual competition was removed -- and have moved up in the world into the houses of the exterminated.

One particular focus in the second “era” falls on University of Vermont Holocaust scholar Raul Hilberg, who analyzes Berlin’s codification of centuries of Old World anti-Semitism and the significance of the suicide of Ghetto spiritual and official leader Czerniaków.

So much is here, and nine-and-a-half hours is so long, that the exhaustive, exhausting documentary weakens itself. Which is not to deny that Shoah (Hebrew for “annihilation”) is a landmark. However, hours should have been cut, most especially among the last ones, where the thrust is blunted. Pans of the remains of the camps make their point the first or second or third time but then become less chilling than the once-shown ovens; superfluous, too, are repetitions of the same footage of rails, entrance gates, a Ghetto house, Ruhr industry,  the interior of a surreptitious camera van.

There is a disconcerting habit of allowing speakers to go on a while before subtitles kick in. And Lanzmann is subjectively leading in his questions, ironic and browbeating; though his cause is just, and war monsters hardly deserve consideration, the director diminishes himself with entrapping lies -- “I promised” -- about not recording and revealing.

Shoah is a difficult watch, at least as much for technique as subject. For all that, few other films match its consideration of unspeakable evil and indifference.

(Released by Why Not Productions; not rated by MPAA.)