"This Means War" is the worst McG film yet. And good Lord, that is saying something. The director formerly known as Joseph McGinty Nichol, who gave us "Terminator Salvation" and "Charlie's Angels -- Full Throttle," brings his pummeling touch to one of the most unnecessary, audience-abusing, incoherent, stupefyingly dumb movies of our young century.

This is a romantic comedy crossed with a spy thriller crossed with a migraine. Reese Witherspoon, her perkiness dialed up to 11, plays Lauren, the head of a consumer product testing lab. In her off hours from blowtorching frying pans, Lauren yearns for that special someone with the ditsy insecurity of a high school wallflower. Her brassy gal pal Trish (Chelsea Handler in a performance as grating as two bricks rubbed together) posts Lauren's profile on a singles site, attracting the eye of Tuck (Tom Hardy), a lonely-hearts CIA agent. Most films would recognize by now the absurdity saturation point has been reached. But "This Means War" presses heedlessly ahead, introducing Tuck's BFF fellow spy FDR (Chris Pine) into the equation. Lauren, who doesn't know they are pals, kind of likes both, and in the spirit of product comparisons, dates them simultaneously, which -- ick.

With neither man willing to step down, they begin a clandestine all's-fair battle for her heart, sabotaging each other with high-tech spycraft and lowdown skullduggery. Shock of shocks, this doesn't turn out to be such a good idea. Science-fiction writers use the term "Idiot Plot" to describe a story that would not hold together unless the main players were imbeciles. For "This Means War" to work, the audience would have to be idiots, as well.

Credible characters might provide a touch of interest for this ludicrous premise, but there are none. Witherspoon's umpteenth mate-selection romcom taps no new reservoirs of charm. Pine delivers his lines with his formidable eyebrows arched, indicating that he understands the film is intended to be a farce. Hardy, an excellent actor when given a chance, plays it straight, which is a more honest rendering of the flat-lining script. The scene in which Witherspoon nails Hardy in the crotch with an errant paintball is not likely to go on either actor's highlights reel.

Theoretically there must be a way to make this movie work, but no one involved has a clue as to what that might be. Each of the stars has been fine in earlier projects, so they arrive on the screen with a sort of dowry of goodwill. After 98 minutes of mirthless tomfoolery, those warm feelings have soured into the blackest bile. There is not a graceful, stylish moment here, nor an image that resembles real life, right down to the flagrantly unconvincing soundstage sets. With its skeevy premise, lifeless action sequences and crass comedy, this is a "War" on the audience.