When Joseph Conrad sent his narrator into the heart of darkness, Africa was unknown territory. Revisiting the scene now, Greg Jackson dispatches his explorer to an even stranger destination: an algorithmic universe. 

Jackson, a Granta Best of Young American Novelists in 2017, won prizes with his story collection Prodigals. His debut novel, The Dimensions of a Cave, could hardly be better timed. New fears about AI give it disquieting relevance. Conspiracy theories mingle with deep state corruption. Gradually it grows into a Chandleresque adventure: down these mean cyber streets a man must go. Dropped into the thick of it, the reader might get the feeling of arriving late at a party where everyone else has already been introduced.

Quentin Jones, a veteran journalist, is telling a group of old friends a mind-blowing story. After his article on the US government’s involvement in a morally murky virtual reality programme is spiked, he’s secretly approached to track down Bruce – the Kurtz figure here – who went into the programme as an observer and has vanished. Quentin’s task: to follow Bruce into the simulation, where people occupy world of synthetic reality. But is he being led into a trap?

In 1909, E.M. Forster’s prescient novella The Machine Stops had Technopolis replacing God. Today, some see the human animal as an endangered species. Relying increasingly on apps and the web, we ourselves are becoming algorithmicised. Jackson’s novel offers an appalling logical extension: enough data will allow networks of power to take a crucial step to the digitisation of everything.

At a pivotal point in the book, looking at the past through the lens of guilt, the elusive Bruce recites a litany of man’s inhumanity to man, an unrelenting summary of cruelty and genocide from ancient rituals to modern degradation and slaughter. No one is innocent here. And information is the new enabling force. For solace, interwoven with the darkness Jackson gives us elegiac descriptions of nature in bud and bloom, changing seasons, the fall of light. Our fragile world. 

The Dimensions of a Cave proposes a variation on Plato: which is the true choice between reality and shadow? The novel is part quest, part metaphysical mystery, but in this deeply scary dystopian world, love still plays a part, as does loyalty. The best news is that Jackson is a terrific storyteller, and you need to keep reading to find out what he has in store for us – horror or hope.