Carsten Nicolai's soundtrack to Marc Weise's award-winning documentary about the Ecuadorian opposition to Chinese investment is a solemn affair, led by grumbly, manicured drones, booming subs and Nicolai's patented glassy sonic illusions.

Weise's film tells the important tale of resistance fighters and journalists in Ecuador who oppose the transfer of resources to Chinese investors, focusing on life in a troubled mountain village. To capture the gravity of the narrative, Nicolai responds not by pruning sounds from the region's folk canon, but by using his own well-worn set of sounds to mirror the film's emotional arc. So opening track 'Ritual' is subtle, almost orchestral ambience that sounds cinematic, but gassy - it's not a million miles from Nicolai's beloved 'Xerrox' series, in fact. But he shows his hand on 'Confrontation 1', bringing in the expected echoing glitches and rumbling, low-end-heavy rhythms, that inevitably arrive accompanied by coarse, industrial feedback. When we're introduced to the village, Nicolai takes a different approach, blending minimized, insectoid drones with breathy synthesized flutes and electronic gurgles that sound like pebbles dashing against rocks. On the lengthy 'Sarayaku Hidding', Nicolai introduces more acoustic elements with delicate bowed and plucked strings that fade into his whirrs and buzzes, leaving spacious, minimalist piano tones to take the lead. Whooshing white noise and rhythmic glitches give all the accompaniment we need for Nicolai's ominous, Sakamoto-like notes. And on 'Demonstration', he creates tension with synthetic chorals, hollow thuds and cinematic strings. As the soundtrack develops, it becomes more and more abstract: 'Sicario' is a mess of radio static and thumping low end; 'Storming Camp' is a psychedelic nightmare, with anxious, buzzing synths and foreboding orchestrals; and 'Legal Process' is a hyper-minimal rattle of skeletal electronic clips and rushing noise. And if that sounds a little too much, we're brought back into the the sunlight with 'Ritual Reprise', hinting at hope on the horizon with its fluttering reversed piano and celestial woodwind blasts.