By Matt Sabljak   Published Mar 03, 2006 at 5:23 AM

As if "Die Hard 3" wasn't convincing enough, "16 Blocks" should set the record straight: Bruce Willis is at his crime-fighting best when he's an alcoholic cop with a nasty hangover and an unwilling black accomplice.

In "16 Blocks," in which Willis is rivaled only by Nick Nolte in "48 Hrs." as how grizzled and miserable an officer can be without being excused from the force, Willis plays Jack Mosley, a New York City detective who is ordered to transfer a prisoner from jail to the courthouse before he can head home after another long, booze-fueled night on the job.

Rapper Mos Def is the prisoner, Eddie Bunker, and he must make it to the courthouse before 10 a.m. to testify against a bunch of dirty cops that have been fixing cases. The clock is ticking as it's past 8 a.m., and once the jury's tenure expires, that's it; the district attorney doesn't have another witness. Case closed. The People lose. Which also means Eddie's plea bargain is nullified, so we can't blame him for being apprehensive when Jack makes a pit stop at the liquor store.

As Jack is purchasing refreshments -- and Eddie's waiting in the car -- a black van stops nearby amid the urban hustle and bustle. A black van is never a good sign. A suspicious character approaches the car, taps on Eddie's window, pulls a gun, and just as he's about to execute Eddie at point-blank range, a shot rings out. It's Jack, right on cue, and we know this morning's about to get a whole lot worse because Jack's bottle of whiskey shattered on the sidewalk amid the ensuing chaos.

Question: What's the only thing worse than a drunk cop? A hung-over cop. And despite their next destination being a local tavern as a temporary safe house, Jack's not elbowing-up anytime soon. Upon arrival of his partner of 20 years, Frank Nugent, played perfectly by David Morse as an arrogant, calculating snake, Jack finds himself in the middle of a stand-off: a handful of his fellow coppers on one side (who would be implicated by Eddie's testimony), and Eddie on the other. Jack chooses Eddie, and the fiesta begins.

Jack's determined to get Eddie to the courthouse on time (and alive), and seemingly the rest of the police force is determined to stop them. Apparently, this behavior is out of character for Jack, as Frank ensures the captain that Jack will eventually "do what he always does." The price Jack pays for trying something new: 16 blocks (that's how far the courthouse is) of pure hell.

Forget Mos Def's slick, off-screen emcee persona; in "16 Blocks," his character is the black equivalent of Forrest Gump, delivering quips that ooze with a hilarious blend of simplicity and profundity. Mos Def's sense of timing is flawless, and though it takes a while to warm up to his nasally drawl, his performance ultimately adds another dimension to the film that makes it worth the price of admission.

Without Mos Def, "16 Blocks" is just another conventional Bruce Willis vehicle; the fecal matter hits the fan, and Willis comes out unsullied -- save for generous amounts of caked-on blood and grime.

Nonetheless, there's no one more qualified than director Richard Donner of "Lethal Weapon" fame to deliver an action-packed ride with a digestible mixture of bullets and comic relief. This is "16 Blocks" of fun.

"16 Blocks," rated PG-13 for violence, intense sequences of action, and some strong language, opens everywhere on Friday, March 3.