The title reminds me of that old Tennessee Ford song, Sixteen Tons. That’s what this film feels like, sixteen tons of something waiting to happen but never does.

Directed by Richard Donner, who helmed the four “Lethal Weapons,” one might think he’d take us on a pretty good movie ride. He does, but the ride is in a luxury car — smooth, noiseless, comfortable and as long as you’re not driving, a perfect place to catch forty winks.

Bruce Willis plays John Mosley, a heavy-drinking, desk cop with a job-related wounded leg who’s depressed and useless at his now non-descript job. To call him jaded is to give him an energy he doesn’t have. Life seems to have been sucked out of him. This looks like a good character part for Bruce and we wonder what he’ll do with it.

Very early one morning, after Mosley’s trudged into work looking and feeling like sixteen tons fell on him, he’s given the scut job of transporting a small time, insignificant, petty criminal named Eddie Bunker to the courthouse in time for him to testify before ten AM.

Mosley starts the brief sixteen block (get it?) journey with Eddie, appealingly played by Mos Def. But Eddie has been marked for death because his testimony will implicate five or six bad cops, among them Mosley’s ex-partner, Frank Nugent, played chillingly by the always chillingly effective David Morse.

Along the way, Eddie chatters non-stop while Mosley drives with the so cool, smirky Bruce Willis silent routine that’s supposed to signify great depth of character. After five minutes Mos Def’s aria, you’re wishing for the sound of fingernails on a blackboard, and we do get a welcome reprieve as Mosley pulls over at a liquor store for a fifth of booze, leaving Eddie alone in the car, an easy target for two approaching hit men. In the only truly movie moment, Mosley exits the store in time to kill one assassin and exchange shots with the other.

Now begins the tedious second act of the film, which is forty minutes of Mosley and Eddie on the run in the crowded sixteen block distance between them and the courthouse. Maybe by now it’s fourteen blocks, we never know. Most of this act is comprised of shots of Mosley and Eddie running through crowds of people while looking around for the pursuing bad cops interspersed with shots of the bad cops in the same crowd looking around for them. Exciting this is not.

At the beginning of this chase section, Mosley is confronted in a bar by his former partner, who reveals the personal importance of Eddie’s upcoming testimony and suggests that Mosley look the other way and go back to the comfort and safety of the bottle. (Incidentally, diversity has penetrated the bad cop population — we have a black, an Hispanic, and an Italian along with the expected New York core of Irish flatfeet.)

But something is ignited inside Mosley and he refuses to knuckle under to Nugent. He escapes with the cowering Eddie and re-enters the crazy quilt of downtown New York on the trip to the courthouse at Centre Street.

Here’s the big problem of the story. So far it looks to us that Mosley has decided to do one last good thing and go out in a heroic blaze of conscience. Fine! Except this character trope is so overdone that its execution better be very compelling to keep our attention. This isn’t.

But Mosley really isn’t just another hero doing a good thing in a bad movie. He’s risking his and Eddie’s life it because of the guilt he’s been feeling these past years over the fact that he’s also one of the bad cops Eddie’s testimony will implicate.

Wow!

No wow. The revelation comes too late, at the end of the film and it’s hardly the “I See Dead People” shocker we got at the end of “Sixth Sense.” Hell, it’s not even a spoiler, which is why I revealed it. A spoiler makes a difference in the story, this doesn’t.

If the writer, Richard Wenk, and Donner wanted the audience to care about Mosley and involve us in his deadly predicament, we should have known about his past and motivation from the beginning. Then, Mosley’s conflicted decisions about turning Eddie over would be character grist the audience could chew over. His actions would contain the suspense of his ambivalence and, indeed, Wenk would have easily written the middle in that more interesting, compelling way.

Instead the end beat is tacked on and has no emotional use to Mosley, the story or the audience. It’s just an “Oh,” moment, robbed of all its emotional juice, like watching someone running down a long road and learning when he reaches the end that the road was littered with landmines. At that point, so what! The run would have worried us more if we knew the kind of road it was.

Ultimately this bad storytelling decision is what kills this promising movie. The elements are all there, but they’re not in the proper sequence. We don’t follow character development in the body of the film, we follow, and fairly ordinary action at that. Character is what keeps us glued to the screen and the story cheats us of all opportunity to know Mosley as well as we could. Bruce’s chance for better performance got cheated