It's hard to comprehend a block here in Arizona, where a block is defined from Walgreens to Walgreens. In New York, at least in this case, blocks are measured by the number of crooked cops between you and the courthouse. And in 16 Blocks, the crooked cops are as frequent as pedestrians, or yellow four-door cars with signage on the roofs.

How our hero cop and his nasally witness traverse the distance in the title is the foundation of the movie, but 16 Blocks is not just a story about New York travel (subways are out, taxis move too slow, walking is risky); it's a story about two bad guys trying to make good on their mistakes. It wins because the chemistry between Bruce Willis and Mos Def is so effective it allows the film to rise above B-grade cop thriller to something marvelous and electric.

Mos Def, a terrific rapper turning into a terrific actor, plays Eddie Bunker, a lifetime criminal trying to make good on his dreams to become a baker. Bruce Willis, an action star growing too old for action films, plays Jack Mosley, a dirty cop trying to make good on the oath he took so many years ago. They meet by chance, and nearly die by something else entirely.

Eddie, a low-level crook, has witnessed a dirty cop doing business and at 10 a.m. he's going to testify to a grand jury about what he's seen. At noon he's going to change his life and move to Seattle. But at 8:30 a.m. he's going to be killed by men sent by the dirty cop. Jack, of course, stops the murder and saves Eddie, which seems to go against his entire career as a bad cop. "Do what you always do, Jack," one cop says, hinting that he's one of them in corruption. The rest of the movie is Jack and Eddie fighting, and faking, their way to a courthouse 16 blocks away.

Rock music puts emphasis on the beat, jazz puts emphasis off the beat. 16 Blocks is jazz music: It's an action film, but its high points can be found in the punctuation, in the quiet moments between chases or shootouts. Writer Richard Wenk has put devastation into words, not the thunderclaps of gunshots. In every sequence exists long passages of dialogue -- from Eddie's tension-breaking birthday cake speeches to Jack's moments of self-realization that he is one of the bad cops. It's a nice touch on a movie that will be written off as a shooter, when it's really an intelligently spoken talker.

As for the action, it speaks for itself in long elaborate sequences on rooftops, in Chinese kitchens and in hidden elevators. The film's greatest image is Jack hunched over the steering wheel of a city bus plastered from the inside with Chinese newspapers to neutralize police sharpshooters. That Jack and Eddie get out of the bus situation is remarkable enough, but when you see how they get out, you will be pleased that the solution is so simple.

The film is directed by Richard Donner, who's only directed one other film (2003's Timeline) since the last Lethal Weapon movie in 1998. How he came to direct 16 Blocks -- and why -- is a question I don't care to ask; I'm just pleased with the results he's given us. It's a fun, invigorating movie that rises high out of the genre it was created in.

I have only one major complaint -- the plot has an easy fix that's neglected: Jack could call the FBI or a TV news station and end the whole ugly affair -- but it's so minor that I will confine it inside dashes. The film also employs several tricks on more than one occasion, double switches behind doors and gunshots that come from unexpected off-screen guns, which is kind of cheap. The relationship between the two leads cancels these minor points out, though.

Eddie is loud and annoying, but he grows on Jack, who admires his willingness to testify, something Jack is not capable enough to do because he's embroiled in the dilemma. Jack, played tiredly and doggedly by Willis, is ethical at inconvenient times and you can see it both aggravates and pleases him at the same time. He's a guy who never wanted to be bad, but it was easy to do so he fell inside its trap.

Watching Jack and Eddie -- or Willis and Mos Def -- click is the reason to go see 16 Blocks, a film that will drop rather unnoticeably into the February/March season of movies typically reserved for garbage. The Oscars are on Sunday, and if I had to tell you to pick one, I would choose 16 Blocks. Who needs dozens of bloated speeches from winners, when great speeches from the two losers in 16 Blocks are so much better?