“Night Will Fall” is almost the ultimate Holocaust documentary without actually being about the Holocaust. Instead, this devastating film is the story of the ultimate Holocaust documentary and how it took almost 70 years to complete despite the involvement of such luminaries as Alfred Hitchcock.

That documentary, with the blandly British title “German Concentration Camps Factual Survey,” was a British production under the guidance of Sidney Bernstein with extensive American contributions. Men in London processed the devastating footage from freshly liberated Nazi death camps as the Allied armies advanced.

“Night Will Fall” shares that devastation in airing hard-to-stomach scenes from the likes of Bergen-Belsen and Dachau (a particularly horrifying moment shows Dachau footage in negative, the way the editors in London would have first seen it).

It’s easy to see why Bernstein felt it was so important to complete his documentary, and it’s hard to accept the reasons that the Americans eventually pulled out of the project, leaving it to Britain’s Imperial War Museums to finish the film almost 70 years later.

We see only glimpses of the final film, but in some ways the story of that film, chock-full of horrifying footage, tells us even more about how the machinations of governments can grind away individuals and develop into mindless villainy.

(Tickets remain for the Feb. 2 screening at Regal Atlantic Station; the Feb. 17 showing at UA Tara is sold out; ajff.org.)

Michael Jacobs