Bone-snapping martial arts violence, a Mack truck trying to run down a beat-up pickup, skin-melting toxic waste, explosions galore, Randy Travis as a bad guy pretending to be a good guy and gratuitous country-western guitar-playing from Steven Seagal. What more could a moviegoer ask?

Well, a little acting might help.

But "Fire Down Below" is the quintessential Seagal movie, right down to his lecture-at-the-pulpit on environmentalism.

Fans . . . does he still have fans? . . . will not be disappointed.

Seagal stars as an undercover federal agent for the Environmental Protection Agency, assigned to investigate rumors of toxic-waste dumping in the Appalachian Mountains of Kentucky.

Well, maybe "undercover" is stretching it, since he stands out like a Redwood in a cornfield.

Dressed in black, sporting a ponytail and talking in his throaty New Yorker accent, Seagal masquerades in a small rural town as a carpenter. He lives in the basement of the local church and fixes porches for poor locals. "I'm just doing God's work," he says.

Meanwhile, he's testing the water in rivers and streams and making inquiries about health problems. And he also beats up the bad guys who are trying to run him out of town. Right in the middle of Main Street. In broad daylight.

Seagal needs evidence and a witness who will testify against those who are bringing in the toxic waste and dropping it into abandoned mine shafts. But too many people are being paid off — though you'd never know it to look at their living circumstances.

It's obviously not enough to hear helicopters flying overhead every night, lighting up the mountains as they drop off the toxic waste.

At one point, Seagal threatens the local sheriff by saying that he can have 300 agents in town immediately. Not a bad idea — maybe one of them would notice the helicopters!

But, no. Seagal remains a lone wolf.

He also finds time to romance a lonely, misunderstood beekeeper (Marg Helgenberger), spend time counseling the misguided local preacher (Levon Helm) and befriend the town idiot (Harry Dean Stanton) . . . who turns out to be not-so-dumb after all.

Orchestrating the toxic waste scheme is a tycoon (Kris Kristofferson) with a high-rise office atop a casino, complete with sexy secretary and bedroom.

In addition to Travis and Helm, other country singing stars who show up in the supporting cast or singing on stage are Mark Collie, Travis Tritt, Marty Stuart and Loretta Lynn's identical twin daughters Patsy and Peggy.

The acting is wooden (Seagal gets more zombie-like with each film), the writing is ridiculous and the fight scenes are redundant. (That silly speeded-up camera technique makes him look like a silent-movie comic, knocking down bad guys like bowling pins.)

And beware of the constant background music — many of the songs were co-written by Seagal!

"Fire Down Below" is rated R for considerable violence, some profanity and vulgarity.