“Identity Thief” is not a great movie. But it is a great vehicle for two terrific actors who drape themselves in material perfectly tailored to them.

The affable film hits all the familiar points of a road comedy: Traveling is hazardous to one’s health, finances and sanity. Strange bedfellows are often forced to share a shoddy motel bed. Yet in the end, odd couples will find common ground. Just as they did in “Due Date,” “Midnight Run” and “Planes, Trains and Automobiles.”

In “Identity Thief,” Sandy Bigelow Patterson (Jason Bateman) already shares common ground with his future traveling companion, Diana (Melissa McCarthy). For one, they have the exact same name … sort of. Diana, a career criminal and pathological liar, has actually stolen Sandy’s identity, plying herself with premium tequila shots and a house overflowing with vanity items.

When Sandy (the real one) finally catches on, he strikes a deal with the police and his new employer to clear his name. Sandy’s plan is to coax the impostor into accompanying him back to Denver, where she can be arrested.

So the family man heads to “the worst place in America” — i.e. Winter Park, Fla. — to retrieve her. Things do not go as planned.

On the surface, Bateman plays another of his mild-mannered office drones hindered from getting a deserved promotion by his jerk of a boss (Jon Favreau). And McCarthy delivers one more abrasive wacko who harbors a secret life. Comfort zone territory, indeed. However, the stars dig deeper.

Decked in her flowered smock and exploding perm, McCarthy hits plenty of comedic high notes, especially when forced to improvise her escalating cons. (Bateman is equally versed at deadpan sarcasm during these bits.)

But she also delivers a confessional scene so well-acted, so revealing, that it brings a resonance to all her character’s actions before and after. It begs comparison to John Candy’s classic “I like me” monologue from “Planes, Trains and Automobiles.”

Director Seth Gordon (who directed Bateman in “Horrible Bosses”) and writers Jerry Eeten and Craig Mazin (“The Hangover Part II”) keep the adventure interesting. Robert Patrick arrives as a hard-nosed bounty hunter sent to retrieve Diana after her skipped court date. And two sexy contract killers (singer T.I. and Genesis Rodriguez) join the chase after she scams them.

In one of the funniest scenes, KCK’s Eric Stonestreet also drops in, virtually unrecognizable from his “Modern Family” role, playing a turquoise-loving “big spender” who picks up Diana at a roadside bar.

Less successful is Amanda Peet as Sandy’s wife. She adds little to the story and misses a perfect opportunity to break out of the thankless role. Note: When first faced with someone intentionally trying to ruin your life, it’s rare to react with a “nice to meet you” attitude.

“Society can’t function without rules,” Sandy explains to Diana.

Neither can Hollywood. “Identity Thief” is fundamentally about stealing, so it’s no surprise that it borrows from other movies. But it sticks to the unwritten rules of a successful road comedy, dispensing ample amounts of humor and humanity along the way.