If you believe in magic, you must read This One Sky Day, easily one of the most gorgeous and lavishly sprawling books of 2021. And if you don’t, Leone Ross’s third novel, set in Popisho, an imaginary archipelago of islands loosely based on Jamaica, where every inhabitant has their own particular “cors”, or magical powers, will at the very least convince you that enchantments lurk around the corner of our workaday lives.

A small and fervent clutch of fans have followed Ross’s work through her first two novels — All The Blood Is Red (1996; nominated for the Orange Prize), Orange Laughter (2001), set in 1990s New York — and a sizzling, sensuous short-story collection, Come Let Us Sing Anyway (2017). Ross, now 51, was born in Coventry in the UK and lived in Jamaica for many years before returning to London in her late teens, and the rich fabric of her Jamaican and British heritage is woven deep into This One Sky Day.

Ross’s early work has many strengths, and the author might have been more widely known were it not for the fact that she takes long pauses between books. Like her short-story collection, This One Sky Day (published as Popisho in the US) took 15 years to come together, but this is definitely her breakout book.

The novel follows two lovers, Xavier Redchoose and Anise Latibeauderre, long separated by their marriages to other partners, over the course of a single day. Within this short timeframe, themes including postcolonial politics, LGBT love and a major character’s struggles with addiction to enchanted moths swirl in a fascinating stew. And, from the opening sentence — which softly echoes the work of Gabriel García Márquez — there is a sense of one magical realist tipping her hat to another: “On the first anniversary of his wife’s death, Xavier Redchoose got up before light and went downstairs to salt the cod.”

In Popisho, a sisterhood of obeah women examine babies and children to see what special talent they might have been gifted by the gods. “Everyone in Popisho was born with a little something-something, boy, a little something extra. The local name was cors. Magic, but more than magic.” Some have prodigious strength or pleasant breath, some can tell the future or time-juggle; some might be healers, others have prehensile tails or extra taste buds.

Xavier is a “macaenus” — the 413th of his kind on Popisho — gifted with the ability to flavour food through his palms, and proprietor of the Torn Poem restaurant. “Everybody said Xavier’s cooking lingered: you could pursue your dreams with renewed fervour, see yourself in a different light; believe in the unachievable.” On this day, Xavier prepares for a banquet in honour of Governor Intiasar’s daughter, Sonteine, with a walk-round his island to seek special ingredients for a feast, and through the stories of many of the islanders, Popisho’s tangled and rich history is revealed.

This One Sky Day brings together an impressively large and voluble cast of characters. Xavier’s dead wife, Nya, leaves a sad question-mark behind her while Anise, the woman he truly loves, has her own quest as a healer. Other strands of narrative concern the mysterious orange graffiti that is questioning the Governor’s rule, bringing politics into Popisho’s colourful universe, if a trifle unconvincingly; the toys that disappear from the Dukuyaie Toy Factory; the governor’s disowned son Romanza who finds a thrilling but challenging love; and a storm that is brewing.

Ross also offers some juicy surrealism. At noon, women across the island feel a key body part, their “pum-pums”, suddenly detach themselves. Some women lament and some shrug it off: “As she sat looking at her newly independent vulva, it occurred to Lyla that it had long been a nuisance.” The Governor announces a 24-hour ban on all sexual activity. But, as with other aspects of the narrative, it’s left to the reader to accept this plot line as part of the strange but compelling magic of Popisho’s capacious world.

Although many readers will relish the language, rich with badinage, wordplay and terms of friendly abuse that any Jamaican will instantly recognise and cherish, Ross’s editor should have pared back the over-seasoned dialogue: “‘Dandu, I don’t believe you! You have our macaenus standing in the yard like a puss’ — her voice rose to a shriek — ‘and you never tell me? Wait, macaenus! Oh my gods, wait!’” Elsewhere, Ross’s descriptions are rich with inventiveness, colour, flavour. Xavier cooks prawns, poached in lime shavings and thyme, coconut cake and tamarind bonbons, oranges doused in rum, which are set on fire, charred and bitter, soft grilled cloves of garlic.

Fantasy and escapism have an unnecessarily bad rap among establishment literary critics, who have often treated books in this genre as the poor cousin of “serious” realist fiction. But in recent years, a clutch of incandescently talented writers, from Erin Morgenstern (The Night Circus) to Susanna Clarke (Piranesi), Kazuo Ishiguro (The Buried Giant) and Marlon James (Black Leopard, Red Wolf) have reminded us that fantasy is one of the oldest and most imaginative branches of human storytelling. Ross has her own “cors”, a gift for creating an unforgettable world, and with this book, she takes her rightful place at that table of writers.

This One Sky Day, by Leone Ross, Faber RRP£14.99/Farrar, Straus and Giroux (under the title ‘Popisho’) RRP$16.99, 480 pages