From “Don Quixote” to “Thelma and Louise,” storytellers have launched their characters on journeys to jump-start plots and force these characters to change.

With “The Revised Fundamentals of Caregiving,” Jonathan Evison also employs the inexhaustible narrative trope of the road trip, around which he wends his tale of hapless 21st-century men — men who cheat, fail their sons and marriages, and inadvertently wreck families. Their lives are vessels for bad behavior. Their craft: the SS Bad Decision.

Benjamin Benjamin is our well-meaning but haunted hero, a failed poet and odd-jobsman who becomes a stay-at-home dad only to lose his wife and kids in a harrowing event he calls “the disaster.” Unemployed and single, Ben says “I’m not qualified to do much anymore.” With that as the set-up, Ben (our first-person, mostly present-tense narrator) enrolls in a class called The Fundamentals of Caregiving to steer his ship toward a better course. He comes to care for his first charge: Trevor, or “Trev,” a 19-year-old kid suffering from a nasty form of muscular dystrophy. The disease twists Trev in knots; Ben calls him a “pretzel with a perfectly healthy imagination” and “an evil-genius grin.”

As the novel leans forward into this new relationship, we glimpse (via flashback chapters) more into what happened to Ben’s wife and two kids, as well as about the man he once was, and the suburban mojo he once wielded. “I played a nifty center field. I was a vortex where fly balls went to die,” he boasts. People even said he looked like Johnny Depp. Now, he says, “it’s hard to care for very long.” About anything. “The world flows right through me like a human dribble glass.” Many nights are spent in the beer-infused throes of what he names (and many men surely recognize as) “the old blur.”

Perhaps it’s expected that the caregiving gig with Trev will kick-start some internal process in our not entirely likable Benjamin Squared. As the two watch the Weather Channel for hours, and trade braggadocio about imagined sexual escapades with unavailable woman, they hatch a faux road trip to visit the kitschiest roadside attractions of the American West. Then, that quest becomes real.

Evison’s prose is replete with his gifts for witty imagery and turns of phrase. An artwork in an Asian restaurant is “at once reminiscent of Gauguin and Hanna-Barbera.” An unfortunate woman with an overbite is likened to “a bottle opener.” In a rare visit with Trev, Bob, his inept and deadbeat dad, ponders the road trip map Ben and Trev have concocted, “tilting his head curiously like a golden retriever confronting a quadratic equation.” We have hitchhikers, as well as bar fights with yokels and comic chases. In one, Ben hunts down the driver of a mysterious Skylark, at night, in a hotel parking lot, wearing only a Speedo.

With its extremely cinematic plot and collection of quirky scenes, the novel might remind you of “Little Miss Sunshine” meets “Rain Man.” And like Hollywood, Evison occasionally veers toward the precipitous edge of sentimentality (often at the end of his brief chapters.)

Yet largely “The Revised Fundamentals of Caregiving” is even-keeled, big-hearted, and very funny, and full of hope. Through Ben, missteps are made, and human foibles are exposed. But we also glimpse that distant shore of hard-earned redemption. For that, Evison’s novel is worth the voyage.