Neil Blomkamp, the South African director behind the clever apartheid sci-fi District 9, has enjoyed – or possibly weathered – a chequered career to date. His debut feature was shortlisted for the Best Film and Best Screenplay Oscars. His cerebral actioner Elysium (2013) was an interesting, messy fan favourite. Chappie (2015) was a yellow-pack Short Circuit. Since then, he’s gone back to skilful world-building and SFX with a series of short films, and had his considerable talents leeched by shelved Alien: Covenant and Robocop sequels.

Demonic, a film secretly shot in far-flung British Columbia during the Covid-19 lockdown, is something of a return to form. Ever the technical whizz-kid, Blomkamp has pioneered something called volumetric capture; a three-dimensional video system through which “the actors are simultaneously recorded with 260 cameras and then turned into geometry”. It’s a visual trick that allows the director to simulate virtual reality on the big screen and it’s fascinating and eerie to look at.

As the film opens, Carly (Carly Pope), the traumatised heroine, finds her mother  (Nathalie Boltt) inside an abandoned mental hospital. It’s a dream, but Blomkamp’s deftly fashioned uncanny valley signals that there’s more to it.

Upon waking, Carly is told by her estranged friend Martin (Chris William Martin) that he has found the mother she hasn’t seen in 20 years; she’s at a facility run by a top-secret pharmaceutical company. A follow-up call from the same hospital asks Carly to visit. They are, it transpires, trialling a bleeding-edge technology that allows loved ones to enter the consciousness of long-term coma patients.

Carly complies and we soon learn that she had good cause to be estranged from her mother – and, more disconcertingly, that she may not be the only visiting presence in mummy’s brain. All hell – in every sense – breaks loose in the final, Assassin’s Creed-ish act.

The appearance of the paramilitary wing of the Vatican feels more like a visit from Monty Python’s Spanish Inquisition than the filmmaker possibly intended. At its best, however, Demonic falls somewhere between Hellsing and Brandon Cronenberg’s Possessor. Co-written with Blomkamp’s District 9 collaborator Terri Tatchell, the film has agreeably creepy blurred ideas about the human experience and the simulated experience. And it’s never dull.

In cinemas and streaming from August 27th