At a crucial point in “The Volunteer,” the second novel from Salvatore Scibona, the title character walks into an adobe hut in New Mexico. “Piñon wood burned in the cookstove. A new smell to him at the time.” Thereafter, the odor “was never to lose its mythy power of turning whatever the moment into an eternity.”

The same power as found in a born novelist: He conveys a world in a detail. Scibona can also take us into the broken heart of a child lost in a foreign airport, the shattering chaos of a night assault during the Vietnam War and the quiet intensity of a working-class New York neighborhood.

Throughout, his ear-perfect dialogue percolates. Still, the moments of ecstasy are what most distinguish this book, one that trots the globe yet misses nothing. Awe suffuses the key scenes so intensely that even a boulevard in Queens can brim with mystic power: “The whole street thick with life. How can you stand to stay inside?”

Not staying inside, one way or another, drives much of what happens. Characters either quit home or get locked out, starting with that child in an airport. The novel opens between departure gates and renders the boy’s pathos with lightning-stroke vividness: “Under his crooked hat his face was anarchic with spasmodic blinks and sniffles.” He appears about 5, and though this is Hamburg, his babbling isn’t in German. He carries no ID, only a mysterious wad of U.S. currency.

This crisis is the first of many muscular tentacles of plot. The remainder of the brief introduction shifts to the boy’s father, an American soldier who served in Latvia and Afghanistan. This soldier, Elroy, has rarely seen his child, he has no real father of his own, and the close of the first chapter finds him a long way from Hamburg. He’s in New Mexico with his former “legal guardian,” Tilly. As for why the boy is not with him, Elroy can only offer a lame excuse: “It didn’t work out, you know?”

The line provokes a bewildering range of emotion, from pity to contempt. The rest of the novel explores similar extremes, across generations and continents. The scope is far grander than in Scibona’s 2008 debut, “The End” (a National Book Award finalist), though the style remains jewel-like.

Scibona next considers the surrogate grandfather, Tilly, more commonly known as Vollie, for “Volunteer.” His Iowa parents meant the nickname fondly. When the kid actually volunteers, however, joining the Marines in a fit of teenage pique, it just about kills him.

This is the late 1960s, and he finds himself pinned down in Khe Sanh, then tied up underground as a prisoner of war. He survives and goes underground in a new way: Taking the name Tilly, he joins “a ‘shop’ that developed intelligence products,” and he is sent to Queens to determine whether a mysterious character is dead or alive. He doesn’t even think to ask why; disassociation is crucial.

The war chapters and their aftermath, in a simmering, polyglot city, seem to me the peak of Scibona’s accomplishment. They stand with the Vietnam reporting of Michael Herr, in “Dispatches,” and the Bronx depictions of Don DeLillo’s “Underworld.” Indeed, DeLillo’s magnum opus makes a good model for this novel, likewise chasing connection across eras and oceans.

Still, when Tilly catches his first whiff of piñon wood, out in the Southwest, the novel’s not much past halfway. At that point, he’s again desperate to reinvent himself. Fleeing cross-country, repulsed by a bloodbath as unconscionable as anything in ’Nam, his first significant encounter is with Louisa, tending the hut fire.

This woman emerges as the second great creation in “The Volunteer,” and the story’s closest thing to a sustaining connection. At once amorous and flinty, a hippie dreamer and a resilient pioneer, Louisa joins Tilly in a hardscrabble effort to escape his ghosts: “Lean years. Love years. . . Let’s do this until we break.”

But Louisa, too, is saddled with a burden out of the past. She’s caring for a baby out of a commune that practiced free love — a boy named Elroy.

Once Scibona’s narrative catches up with itself, and with the abandoned child, the most affecting player becomes a worldly German priest. He’s the one open to ecstasy and its “mythy power.”

As for Elroy, learning his hard road doesn’t soften his threatening edges. Insofar as this novel is a tragedy, he’s the dark heart. But work like “The Volunteer” can never be one thing only, upbeat or down. It’s teeming, brilliantly.

John Domini  will publish his fourth novel, “The Color Inside a Melon,” in June.

The Volunteer

By Salvatore Scibona

Penguin Press. 432 pp. $28