A mixture of creepy fireside tale and ecological forewarning — shot through with supernatural horror — Paul Kingsnorth’s Alexandria completes his hugely acclaimed and award-winning Buckmaster trilogy.

The series began with The Wake (2014), about the displacement of a Saxon landowner, Buccmaster of Holland, in 11th-century Lincolnshire during the aftermath of the Norman invasion, and was followed up in 2016 with Beast, a story about Edward Buckmaster, a hermit facing a nameless foe, set in our own time. Now it is the 31st century, but the backdrop could be prehistoric Britain, albeit one in which the seasons have been replaced by a perpetual heatwave.

In the far east of England a thousand years in the future, a tiny community named the Order — perhaps the last humans on Earth — ekes out a post-apocalyptic existence on the edge of what was once known as the Fens. Its people worship a semi-pagan religion where birds appear to them as gods; they hunt and fish for their sustenance, which, since the climate has turned tropical, now includes yams and sugar cane. But their number has dwindled drastically in size, due to the disappearance of many who have gone in search of Alexandria, a fabled, mythical city where no one ever dies.

Its remaining members — Yyrvidian, a visionary or “Dreamer”, two elders (“Father” and “Mother”) a couple, Nzil and Sfia, their small daughter, El, and Lorenso, a hot-headed young man — cling to the land and the “mere” (lake) and “holt” (wooded hill) which is their Earth-bound home. The Order is cloistered, yet there is digression. Lorenso and Sfia have become lovers, and the balance of their community has been disturbed. “To be woman is to be beast, to be man is to be wight, to be human is to be animal. that is what we teach here, how we grow in this Order. this heat was not always here, air was not always wet, beneath Waters are forests and cities from Atlantean times.”

Slowly, the strength and unity of the group begins to disintegrate, leaving it open to interference from the overarching enemy, the unseen all-powerful Wayland, whose emissaries have repeatedly preyed on the Order’s former companions, reasoning with them to leave their bodies and “ascend” to the immortal city of Alexandria. A legendary master blacksmith from Norse and Old English folklore, who appears as a vengeful spirit in The Wake, Wayland, by the time of the third novel, is controller of what the Order terms the Machine, and what we know as artificial intelligence.

To withstand the threat of Wayland, the Order must hold firm and fast to its portents: one of which is that the reappearance of swans, long extinct, will herald the falling of Alexandria, after which the Order will be left in peace within its green dreamland. As the novel proceeds — and the flood waters rise — the tale evolves into a terrifying struggle between body and mind, feeling and reason, cold logic and blind faith.

If the plot is complex, the writing is a linguistic delight. Kingsnorth has spoken previously of the “shadow tongue”: his mixture of Old English and invented syntax that was used in The Wake. He returns to this in Alexandria and there is soon a pleasurable familiarity with the “hungry ghasts” (the river ghosts which seek to spirit the child El away) and the poetic homilies from Father and Mother which are drummed into straying, fraying minds.

It comes as a shock, therefore, when halfway through the novel, K, a “retainer” of Wayland’s in skinless human form beneath its red cloak, joins the narrative. K delivers clipped, business-like and jargon-heavy reports on its “targets”, and its ability to reshape itself into whatever these targets most desire — for lonely El, a cat, for Sfia and Lorenso, holograms of each other — gives the book some of its most tense moments.

In a recent interview Kingsnorth explained: “I suppose I’ve been looking for Eden all my life. I think we all have. But it is not available to modern people except in memory or longing.”

The small community struggling at the end of human history, with its temptations and its steadfastness, is reminiscent of Little Gidding — both the 17th-century closed Anglican order in eastern England and TS Eliot’s 1942 poem. It also brings to mind the ancient Britain of Kazuo Ishiguro’s The Buried Giant (2015) and that of the Middle Ages in John Fuller’s Flying to Nowhere (1983) — works in which mystery, loss and devotion all play their part.

If there is a nagging doubt about Alexandria it is with the gender essentialism that underpins the book — man is fire, woman is water, woman is seductress, man is seduced — each has their fixed place in the world. But as a story about human failure and enduring belief, it succeeds. Kingsnorth’s novel is both of time and out of time, and it posits some of the most urgent questions of this millennium: where are we going, and what will become of us.

Alexandria, by Paul Kingsnorth, Faber, RRP£16.99, 408 pages

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