India, April 18 -- Amitav Ghosh's new novel Ghost- Eye is foremost a love letter to fish - first celebrated in the deepest Bengali sense, culinarily, before being mourned ecologically. In a wealthy, strictly vegetarian Marwari family home, three-year-old Varsha Gupta, over lunch, demands fish and rice. "Ami machh-bhat khabo. Machh dao," she declares, refusing to eat anything else. The family, part Jain and fully alarmed, summons a psychologist. Shoma specialises in "cases of the reincarnation type", having worked with an American professor, one of the world's leading experts in the field. So begins this vivid, visceral and deeply satisfying novel. Varsha claims to have been, in her past life, the daughter of a poor fishing family in the Sundarbans, and seems to have an unusually vast knowledge of fish. Shoma devises a plan. She begins poring over books on the aquatic fauna of Bengal and, with her cook, carefully selects different varieties from the fish market, to quiz the child. She carefully prepares a lunch menu with three varieties: Labeo rohita, Cyprinus carpio and Oreochromis niloticus. Varsha, as Shoma suspected, turns out to be a fish prodigy. The fried fish with spices, Varsha recognises, is rui and not catla, a difference that even seasoned ichthyologists often can't spot. She is also able to tell that the doi machh is made with karfu instead of the more commonly used catla. She cannot identify the tilapia, an African variety cultivated in fish farms and newly introduced in Calcutta. It was cooked in a spicy gravy of tomatoes and onions in the hope of passing it off as the Bengali koyi. But Varsha knew the unfamiliar fish wasn't a koyi. She also knew that koyi can climb trees; she says she remembers one climbing the tree next to the pond near her house in her previous life, where it would get as far as the branches, and fall back into the water like ripe fruit. Half a century later, during the pandemic, Shoma's nephew Dinu, a middle-aged antiquarian in Brooklyn, gets a phone call. Tipu, a feckless young firebrand - the semi-adopted son of a friend he knows well - is now a climate activist in the Sundarbans, where he is originally from. To survive the climate apocalypse, he says, "you've gotta be in a place you know well, and if that place knows you too, it'll help you. I mean isn't that what forests and deserts and oceans have always done? Haven't they always taught people who are willing to learn how to survive even when the going got rough?" A snakebite has turned him into a ghost-eye. One of his eyes changed colour, marking him as a kind of seer. He is now part of a network of ghost-eyes who can see both in the ordinary world and a deeper one. A cyclone is coming. Natural disasters have a history of making themselves known via premonitions. And Shoma, seemingly delirious in her old age, saw Cyclone Amphan coming. The devastating super cyclone hit the Bay of Bengal in 2020, leaving millions destitute. Tipu needs Dinu to find out what happened to Varsha, who disappeared shortly after she remembered her past life and began to have premonitions. Her memories are their key to saving the Sundarbans, Tipu says. Preferring to write rather than talk to Tipu, Dinu starts to do just that. But, "would this omnium-gatherum of apparitionists and spirit-whisperers ever be able to accomplish anything practical?" he wonders. Ghost-Eye plays out in the sweet spot between the real and the magical - like its predecessors, but perhaps most successfully. This is the third novel in the world Ghosh has been building, with The Hungry Tide (2004) and Gun Island (2019). Dinu is Deen from Gun Island and Tipu is still a propulsive force. The legend of Manasa Devi, the goddess of snakes, resurfaces. Piya, the dolphin biologist protagonist of Hungry Tide, has a cameo. Like its predecessors, Ghost-Eye lives in the friction between rationalist Westernised modernity and Indian traditional ecological knowledge. Ghosh's 2016 non-fiction book, The Great Derangement, was about literary fiction's failure to grapple with climate change. He argued that the conventional realist novel was not equipped to deal with climate change, while magical realism would undermine the terror of it - that it is "actually happening on this earth, at this time". Ghost-Eye's subversive move is to expose the limits of Western knowledge itself. Ghosh decolonises psychiatry by refusing to pathologise. Past life memory is not psychosis; premonitions are not anxiety, but simply alternate, deeper - spiritual but no less legitimate - realities. Making sense of what is happening to the planet, he argues, requires us to look for what modernity has spent centuries missing. The numinosity seems to belong quite naturally in the sepia-toned Calcutta of the 1960s and '70s - a city then in the shadow of displacement and exile - incarnated particularly in Dev, the Burmese household factotum at Shoma's home. This sense is only heightened in the sections relating to the pandemic, when, inexplicably, drones as big as buses appear in the sky. And when, at a Chinese fish shop, a snakehead, at the sight of Dinu, flails and thrashes about in its tank with such force that it falls onto the floor. It's all strange, sometimes eerie, but oddly believable, as is Ghosh's optimism, despite all good reason. Dinu, gathering family stories, history and memory, is able to build a convincing case through his writing and effect change. Tipu, annoying Tipu, embodies future generations: the kids are weird, but the kids are all right. And then there is the food. There's a particularly vivid scene: Dinu, to recreate dishes of his childhood to evoke once again memory across time and space, watches cooking videos posted online by rural Bengali women. To make mustard oil, not easily available in the US, he orders mustard seeds and gets to work, "heating, grinding and wrapping the oily slurry in cheesecloth before squeezing with all my might. The final extraction occurred in my bathroom, with me stomping barefoot on a colanderful of mustard-seed pulp." This is food writing so fine and so viscerally alive that even I, a reader as vegetarian as the Guptas in the novel, found myself embarrassingly hungry....