John Irving’s 12th novel is a shaggy, shambling, lovable bear of a book. Inspired in part by Bob Dylan’s song “Tangled Up in Blue,” it is vintage Irving, stuffed to overflowing with a cast of memorable characters, dark humor, a surfeit of tragedy and loss, and enough love, sex and death to fill at least two or three less ambitious novels.

Spanning half a century beginning in 1954, LAST NIGHT IN TWISTED RIVER is the picaresque (and almost impossible to summarize) story of a cook, Dominic Baciagalupo, and his son Daniel, who flee a logging camp in northern New Hampshire the night 12-year-old Daniel accidentally kills his father’s sometime lover with an eight-inch cast-iron skillet. The pair, whose close relationship anchors the novel, spends decades in the shadow of the vengeance sought by Constable Carl, Twisted River’s sadistic and misogynistic lawman and the boyfriend of Daniel’s victim. Their journey takes them from Boston to Iowa City to Vermont and then to Toronto as they manage, with the aid of a crusty logger named Ketchum, to stay at least a few steps ahead of their pursuer.

The novel is as intricately and masterfully constructed as a Victorian mansion, erected on Irving’s characteristic foundation of flashbacks and foreshadowing. He pays homage to literary forebears like Dickens in inventing a roster of characters with memorable names (such as “Six-Pack Pam,” “Injun Jane,” the “Yokohama Sisters” and “Lady Sky”) and in his portrayal of working class life, from the perils of logging drives to the pungent aromas of restaurant kitchens.

All of the novel’s characters, even the most sympathetic ones, are weighed down by the burden of their poor choices and occasional bad behavior. From the window of his writing shack, Danny, now a celebrated author under the name “Danny Angel,” can see a small pine tree bent almost at a right angle to itself and that tree. The tree has a “simultaneously tenacious and precarious grip on its own survival,” which deftly sums up the world these characters inhabit.

There are bears, a bit of wrestling, terrible accidents, and an unflinching view of the perversity of fate. There’s a Blue Mustang to replace Garp’s Under Toad from Irving’s THE WORLD ACCORDING TO GARP and even a flatulent dog, Hero, which brings to mind the Berry family’s Sorrow from THE HOTEL NEW HAMPSHIRE. But the novel isn’t merely Irving’s attempt to trot out a bag of shopworn tricks to satisfy fans who have stuck with him from one novel to the next. Each of these familiar elements is given a fresh, reinvigorated life here in the service of a warmhearted, emotionally mature work, and reveal why Irving’s characterization of Danny (“He was a craftsman, not a theorist; he was a storyteller, not an intellectual”) is a fitting bit of self-portraiture.

Irving, who has made no secret of his annoyance with readers and critics who have plumbed his works for evidence of autobiography, doesn’t even make a tepid effort to blur those lines here. Danny attends the same prep school (Exeter), college (University of New Hampshire) and graduate writing program (Iowa Writer’s Workshop, where Kurt Vonnegut makes a cameo appearance), and the course of his literary career tracks that of his creator. The fact that Irving has made these correspondences so obvious is a not-so-subtle poke in the eye to those embarked on what he perceives as a fool’s errand. Yet, as we come to know Danny Angel the writer, we sense we’re being granted more than a peek at the creative process of John Irving. “Somehow what struck him about Daniel’s fiction,” Dominic thinks, as he reflects on his son’s novels, “was that it was both autobiographical and not autobiographical at the same time.”

LAST NIGHT IN TWISTED RIVER is easily Irving’s best work since THE CIDER HOUSE RULES and A PRAYER FOR OWEN MEANY, and is the novel most reminiscent of THE WORLD ACCORDING TO GARP. He’s still asking the same unanswerable question: How do we live happily in a world shadowed by disaster and tragedy, “a world of accidents,” as Dominic sees it, amidst what Irving never ceases to remind us is the “fragile, unpredictable nature of things?” Once again, in a way that’s held throughout a long and illustrious career, John Irving strikes a blow for the notion that robust popular fiction and literary merit need not be estranged. And as befits a story told by a writer who says he began this novel with the last sentence and then wrote toward it, don’t be surprised if, when you turn the final page, the urge to go back to the beginning and start again is nearly irresistible.