Realistic epics and nervy feats of experimentation tend to get awards, but the comic novel may be the hardest work of fiction to pull off well. (Consider Elaine Dundy, Kingsley Amis or Sam Lipsyte, three writers who've made being funny serious business.) Jonathan Evison's third novel, "The Revised Fundamentals of Caregiving," is a showcase of what makes a good one tick: Characters just a touch disconnected from reality, a prevailing sense of life's absurdity and a handful of rude jokes.

Benjamin Benjamin, the novel's narrator, embodies all those requirements. He's hit the skids, thanks to the recession, a tragedy involving his young children, and a separation from his wife, so he's scrambling to find work as a caregiver in Washington state. "The world flows right through me like a human dribble glass," as he puts it, capturing his self-aware, sad-sack mood.

Salvation (or at least a chance to make the rent) comes via Trev, a 19-year-old with muscular dystrophy. Trev's life is defined by routine -- getting him set in a wheelchair, indulging his fixation with the Weather Channel -- which helps put Benjamin's life in order as well. Evison is a keen observer of how the limitations of caregiving can be a kind of liberation: "People will do most anything for a guy in a wheelchair as long as he doesn't have food in his beard," as Benjamin puts it.

The novel's plot is pure hokum. Benjamin and Trev hit the road to catch up with Trev's estranged father, and on the way from Washington to Utah they pick up a few strays: a glum young teenage girl, a pregnant woman and her dim-bulb boyfriend. (Their names alone reveal them as quirky outsiders: Dot, Peaches, Elton.) Benjamin is trying to shake his wife's demand that he sign divorce papers, and the Buick on his tail is making him sweat. It's no spoiler to say Benjamin eventually confesses the depth of his tragedy and that, through this oddball set of passengers, he learns to push past it. The van may as well have "Redemption Vehicle" written on the side.

What the novel lacks in surprises, though, it makes up for in a revealing brand of humor: Evison's episodic chapters and pithy sentences are engaged with the ridiculousness of life's random turns. Benjamin's self-deprecation pulls the dressings from his wounds and makes for some great laugh lines as well: "I'm about as poetic as a forklift," "I can feel her pity like a warm stick of butter sliding down my esophagus." "I planned like hell for something else entirely," Benjamin says toward the end of the novel, and Evison proves that some of the best comedy emerges from lives that have jumped the rails.

Mark Athitakis is a reviewer based in Washington, D.C. He blogs at markathitakis.com.