(Farrar, Straus and Giroux)

If journalists tell us the news of the world, it falls to artists to make sense of that news. Indian writer Amitav Ghosh is eager to take up the challenge.

“Gun Island,” his ninth novel, deals with two of the biggest issues of the current moment: climate change and human migration. But it’s not homework. Ghosh is mindful of his task as a novelist — to entertain. The confidence with which he shapes a good, old-fashioned diversion around these particular poles is instructive. Escapism has its virtues, but a book unafraid of ideas can be bracing.

The novel’s narrator is Deen, a 50-something rare-book dealer. He lives in Brooklyn, but we meet him in Kolkata, where he winters, and eventually follow him to Venice — the global village and all that. In India, a relative tells Deen the folk tale of Bonduki Sadagar, or the Gun Merchant.

The Gun Merchant is said to have run afoul of Manasa Devi, a goddess who rules over snakes and poisonous creatures, and his trials are recorded on the walls of a small shrine on an island in the Sundarbans. This mangrove forest is where India and Bangladesh meet, and the story, appropriately, braids together Hindu and Muslim cosmology.

The Sundarbans are now one of the world’s vanishing regions but have always been difficult terrain. The 1970 Bhola Cyclone killed half a million people in this corner of the globe. But the story Deen hears, from yet another relative, is that a small pocket of survivors rode out the storm inside the aforementioned shrine, protected by Manasa Devi.

Deen is respectful of folklore but still skeptical. “The story’s appeal is, I suppose, not unlike that of the Odyssey, with a resourceful human protagonist being pitted against vastly more powerful forces, earthly and divine.” Ghosh is not exactly subtle about stating his intention here, but sometimes a little clarity is nice. “Gun Island” is to be, like the Odyssey, the tale of men buffeted by the forces of nature and nation.


The author Amitav Ghosh. (Ivo van der Bent)

Early in the book, Deen is guided to the elusive island, not yet swallowed by a rising sea, by a native of the region named Tipu. The rest of the novel is a quest: Deen’s search for the meaning in the myth, and Tipu’s search for safe passage into the West. Deen is a proxy for the reader. He has faith in borders and logic, despite a world increasingly porous and strange.

“I am sorry if this does not conform to stereotypes of Indians — but I am not religious and don’t believe in the supernatural,” Deen tells Cinta, an Italian friend (alas, the least convincing player in the book, almost! everything! she! says! accentuated! with! an! exclamation! mark! because those Italians are a passionate lot). He doesn’t truly believe in a divine being who can corral snakes and spiders to do her bidding. Nevertheless, there are moments this goddess seems to be his adversary.

The world requires explanation, so we turn to language, whether it’s a holy name or a phrase like “climate change.” The feat of Ghosh’s book is in showing us that 2019 is as bizarre and incomprehensible as the 17th-century world, which Deen’s research reveals was the Gun Merchant’s milieu.

The events of the novel don’t wholly replicate the beats of the Gun Merchant’s tale, but the echo between these fictions gives “Gun Island” a particular charge. Ghosh is a practiced and capable writer; by the seventh page, we’re deep into Bengali folklore, and willing to accept this as a novelistic subject. That Ghosh is able to sustain the book’s momentum when its primary inquiry is so cerebral is no mean feat. The novel made me think of A.S. Byatt’s “Possession,” or Tom Stoppard’s best plays, texts that treat academic pursuit as something thrilling.

Deen’s quest also involves Piya, a marine biologist whose research involves tracking river dolphins fleeing pollution in the Sundarbans. “Wouldn’t you be stressed, if you had to abandon all the places that you know and were forced to start all over again?” she laments over the creatures (who deliberately beach themselves in a genuinely affecting turn). The writer doesn’t want his reader to miss that the animal’s plight is no different from the migrant’s.

Subtlety has its virtues, but the authorial heavy hand — in addition to the doomed dolphin, there are forest fires in Los Angeles, a flooding Venice, boats ferrying migrants to Europe, even a moment involving a book from 1592 that feels like something Dan Brown might enjoy — does not grate. Of course, this is what the headlines are like these days. The truth is stranger than fiction, and “Gun Island” is a novel for our times.

Rumaan Alam is the author of “Rich and Pretty” and “That Kind of Mother.”

Gun Island

By Amitav Ghosh

Farrar Straus Giroux. 320 pp. $27