A group of scientists visits the distant planet Arkanar, and discovers a society still trapped in its own medieval era. Unable to interfere with the course of its history, they can only watch in mounting horror as all sparks of intelligent and independent thought are mercilessly snuffed out by Arkanar’s cruel rulers. Will they remain enmired in their squalid existence for ever, or can the visitors subtly nudge the more open-minded in the right direction? Truly, it’s hard to be a god.

Legendary Russian sci-fi authors Arkady and Boris Strugatsky (whose Roadside Picnic was filmed as Stalker by Andrei Tarkovsky) wrote the source novel, and adapting it was director Aleksei German’s dream project for decades. It would take six years of shooting, a further six of post-production and a posthumous premiere before his masterpiece was finally unveiled.

But masterpiece it is: a visually astonishing, almost tactile recreation of an unnervingly recognisable alternative universe, drenched in blood, mud and the tears of the oppressed.