The long-form documentary is enjoying something of a renaissance thanks to Netflix, but there is still nothing to compare to the immersion of sitting in a cinema for eight hours over two days.

In both runtime and theme, Dead Souls is the ne plus ultra of seasonal counter-programming. Shot between 2005 to 2017, this monumental film visits more than 120 survivors of re-education camps and many of China's provinces. In common with the subjects of Claude Lanzmann's epic Holocaust chronicle Shoah, those who testify are elderly: one dies not long after he appears on camera, and the film-maker gives extensive space to his funeral.

Dead Souls is seldom as impactful as Lanzmann's project. The survivors of the Jiabiangou and Mingshui re-education camps are not victims of a systemic extermination policy; they are convicted rightists, who, some 10 years after the Revolution, are confined in the Gobi Desert facilities. The situation there is not as catastrophic as the Cultural Revolution.

But between famine and ongoing skirmishes, many starve, shrink and die horrendously, both in the camp and beyond. There are repeated accounts of abandoned towns and houses around the provinces.

Wang Bing prioritises oral history over available documents: there is no archive footage or structure beyond each lengthy testimony. We’re often listening to second-hand stories and imperfect recollections. Dates are muddled. Details are disputed when more than one survivor appears on screen.

There are multiple and indisputable accounts of starving people eating the recently dead but one man’s tale (as told to him) of a the youngest of five daughters offering herself as food sounds more like a folk tale than a historical detail.

Most of the horrors recounted relate to lack of food: a broth made with beetroot leaves, the stripping of bark from trees, misappropriated noodles, the killing of a sheep, and, most disconcertningly, acts of cannibalism.

Dead Souls emerges as part of a larger, urgent national project to chronicle the re-education camps before the survivors are gone. Yang Xianhui's novel Woman From Shanghai: Tales of Survival From a Chinese Labor Camp was published in 2009 and Ai Xiaoming's documentary series Jiabiangou Elegy: Life and Death of the Rightists premiered in Hong Kong last year.

Essential, if sobering work.

Opens December 14th