The greatest asset of "Mr. & Mrs. Smith" is its premise: Two assassins who work for rival agencies are married to each other, neither one knowing that the other is a hired killer. From that idea a thousand different plots could be launched, and this film chooses one that is devilishly, absurdly, violently funny.

John and Jane Smith are played by Brad Pitt and Angelina Jolie, whose alleged off-screen romance allegedly began during the alleged filming of this alleged movie. Put that aside, though, and watch two savvy actors at work, both handling the comedy and action with equal aplomb. They give excellent performances, he with his every-dude casualness, she with her hot-babe intensity. I'm sorry, Jennifer Aniston, but the two have chemistry. (P.S. to Jennifer: Call me.)

The two killers met in a chance encounter in a hotel bar in Colombia several years ago, and now they are married, living a drab suburban existence in New York state. Each thinks the other has a normal job. They both know their marriage is crumbling, succumbing to the tedium and lifelessness that can creep in when neither party is paying attention. They have conversations like this, regarding the new drapes Jane has just bought:

"If you don't like them, we'll take them back."
"OK, I don't like them."
"You'll get used to them."

Things heat up, however, when both assassins are assigned to the same mission and John and Jane discover each other's true profession. Now John's people are telling him he has to kill the rival agent, even if she is his wife, and Jane's getting the same directive from her superiors. These are people who sorta want to kill each other all the time anyway, what with her lousy cooking and his masculine insensitivity, and now they've been given the go-ahead.

From there the film follows the logical progression, Simon Kinberg's screenplay earning laughs simply by doing what makes sense in each situation. There is a hilariously brutal shoot-out and fistfight between John and Jane, followed by a fiery reconciliation, and a delightfully over-the-top car chase in a minivan during which they discuss their relationship and come clean to each other on all the lies they've told over the years.

"I was married once before."
"What's her name and Social Security number?"
"No, you're not going to kill her."

This is director Doug Liman's fourth major film, and his career seems to have prepared him for it. It has the verbal agility of "Go" and "Swingers," and the volatile action of "The Bourne Identity." (It is because of his work on "Swingers" that Liman knows how to use Vince Vaughn properly, and Vaughn has an amusing supporting role here as one of John's co-killers.) The movie sags just a bit in the middle, when it's still setting up all the pieces, but that third act -- with the car chase and its subsequent shooting-and-talking -- is a slam-dunk, a combination of loud violence and old-fashioned domestic squabbling.

Grade: B

Rated PG-13, scattered profanity, one F-word, a lot of fighting and action violence, a little mild sexuality

1 hr., 55 min.