In “Translation Nation,” an account of the Latino experience across America published in 2005, Héctor Tobar recalled his father, a Guatemalan immigrant, telling him: “We are part of a bigger world . . . full of beauty and horrors. . . . Our history and our future cannot be contained within borders.” The author goes on to say, “I grew up believing it was my destiny to advance this essentially Latin American story into new, northern territories.”

Now, in his third book and second novel, “The Barbarian Nurseries,” Tobar is as good as his word. Once again, he explores the boundaries that bind and divide families, neighborhoods and Southern Californians; this time, to darkly hilarious and moving effect.

The story, told in three parts, begins in a gated community in Orange County, where we meet pale-skinned, half-Mexican Scott Torres; his wife, Maureen; and their three children, Brandon, Keenan and Samantha. Having dismissed the gardener and the nanny, Scott and Maureen are making do with one domestic in these tough economic times.

Enter housekeeper Araceli Ramirez, who, they’ve calculated, can be counted on in a pinch to keep an eye on the kids. Even so, Maureen can’t quite get with the program. The neglected garden embarrasses her; impulsively, she decides to replace it for a four-figure sum. When Scott’s credit card is subsequently rejected after a business lunch, tempers flare and he accidentally pushes her into a glass coffee table, which shatters. Scott drives away to lick his wounds in the company of an adoring co-worker, while Maureen empties their piggy bank and heads off to a spa, baby Samantha in tow.

What is the poor housekeeper to do? She didn’t sign on for this. She doesn’t even like children. Four days later, with no word from either parent (each assumes that the other stayed home), Araceli sets off with the two boys in search of their grandfather Torres, who, she naively reasons, must still reside on a street in a distant Los Angeles neighborhood where he posed for a family photograph three decades earlier.

So begins a wild and crazy ride, which gets wilder and crazier after the boys are returned to their parents and Araceli is jailed on kidnapping charges. In a moment of rare fluency, this illegal from south of the border describes herself as having landed in “a very strange North American circus.”

In this ode to L.A., as affectionate as it is terrifying, Tobar’s position is clear: An exclusive enclave with vast ocean views is no less scary than the flats of South Central, its isolated inhabitants all the more alienated from each other and themselves.

In fact, the farther we get from the order and calm of the Torres family’s McMansion, the more believable, if bizarre, events become in Tobar’s vivid rendering of people and place.

Although epic in scope, this is, at heart, the story of two women: Araceli and Maureen. And never were there such a couple of unlikely heroines: One is inscrutable, withholding and thick-waisted; the other is spoiled, controlling and perfectly accessorized. Lucky for us, Tobar, a Pulitzer Prize-winning journalist, is that rare male author who credibly inhabits a woman’s point of view — both women, in fact, and a slew of other characters besides. If we spend more time with some than with others, it’s a credit to Tobar that we feel we know them all: neighbors, friends, politicians, passers-by — a cast that includes a rabid prosecutor, a pregnant public defender and a social worker who deserves a novel all to herself.

Each moment surprises, right up to a scene close to the end when domestically challenged Maureen faces off with an army of ants invading her beautiful house: “Every day they conquered new territories of tile, particleboard and porcelain,” Tobar writes. “They gathered in pulsating masses around pieces of chicken underneath the dining room table, over the toilet paper in the bathroom trash cans, and inside the kitchen sink, carrying away whatever it was that settled at the bottom of the garbage disposal.”

Baffled by the chalk lines that Araceli drew along the baseboards, Maureen scrubs them away along with the ants, who keep coming back for more. At last, she resorts to pesticide, “so desperate to see the chemicals work that she didn’t bother to get the children out of the house before she began spraying.” Maureen is on border patrol, resolved to keep appear­ances up and the aliens out.

Sad, funny, seemingly inevitable — such are the metaphors and insights from Héctor Tobar, an author from whom we expect nothing less, and look forward to more.

Lenney, the author of “Bigger than Life: A Murder, a Memoir,” teaches at Bennington College, Pacific Lutheran University and in the Master of Professional Writing Program in the USC Dornsife College.

THE BARBARIAN NURSERIES

By Héctor Tobar

Farrar Straus Giroux. 422 pp. $27