Cheap, short and slow, “Hot Pursuit” is a comedy that never lets you forget that pairing up Sofia Vergara with Reese Witherspoon should have worked better than this.

A mismatch/misfire badly misdirected by the director of “The Guilt Trip” and “27 Dresses,” it wastes the Oscar-winning Witherspoon and the spirited Vergara, who are cast as a comically disgraced cop and the wife of a drug lord’s accountant.

It’s “Midnight Run” without enough running, “The Heat” without any heat.

Witherspoon is officer Cooper, introduced in a cute growing-up montage as the adoring daughter of a policeman father who did ride-alongs with him, pretty much from birth. A little too “intense,” she’s been reassigned to clerk duties in the San Antonio Police Department evidence room. Until she’s summoned to help a federal marshal (Richard T. Jones) escort a witness and his wife to Dallas.

The job goes wrong when assassins show up, and Cooper and Mrs. Riva flee in Riva’s vintage Cadillac convertible.

The movie goes wrong right about here, when the script for an 87-minute-long movie spends minutes explaining away the women’s cellphones. Cellphones might clear this whole mess up — or shorten an already undernourished comedy.

Vergara is a shrill Spanish-spewing caricature of the Angry Loud Latina, a variation of the same type she plays on TV’s “Modern Family” — but no one has ever played this type funnier. (“Nice po-leeeese work, Meester Churlock Holmes!”)

Witherspoon puts a lot of effort into playing manic and by-the-book, practicing police 10-codes “as a relaxation technique,” delicately coming up with a feminine reason to be allowed into the bathroom — “some lady business of the tampon variety.”

This never was going to be a smart comedy, but it could have worked. The script is starving for funnier lines and situations, so the two pros strain with bits of physical shtick — trying to drive a bus handcuffed to each other, making out to distract a rancher holding a gun on them.

No money was spent on villains or other supporting players, and director Anne Fletcher undercuts the stars’ timing. Whatever might have been, the flop-happy Fletcher never lets “Hot Pursuit” get up to speed.