I have seen the future of rock 'n' roll, and it's wearing a rainbow-striped shirt.

Maybe that's overstating the impact of a Metallagher show, but if there's a more entertaining new band in town right now, I haven't seen it. And I won't want to see it unless they bring fresh fruit to the stage.

Like Canadian bacon and pineapple, or Lyle Lovett and Julia Roberts, Metallagher is a simple enough combination, but who would have ever put the two together? It's a Metallica cover band fronted by a Gallagher impersonator. You remember Gallagher, the '80s comedian with the fuzzy moustache, funny hat and long, balding hairdo (a k a the Phil Collins cut). Since his jokes weren't funny, he also smashed watermelons for a living.

Metallagher is a joke within a bunch of bad jokes within a pretty good cover band. But it's not as if you'll really notice their musicality. They play again Monday at the Triple Rock, opening for another hammer-wielding act, Thor, the '70s rocker who dresses like the mythological Viking. I'm not making this stuff up.

The quintet's show last week at 4th Street Station -- only its fifth gig -- started with sheets of plastic being duct-taped to the p.a. system. Just before set time, the members carried in a bundle of grocery bags from (where else?) Rainbow Foods.

"Who here has heard 'The Black Album?' " the rainbow-clad frontman asked as he took the stage. "Get the [expletive] out of here if you have."

It's all old-school Metallica, in other words. The band tore through the opener, "Blackened," with adept thrashiness. Even the faux-Gallagher sounded passable singing James Hetfield's parts. Everything seemed normal until the guitar solo. In Metallica, guitar solos belong to Kirk Hammett. In Metallagher, they're all about the hammer.

"Blackened" saw the first of several watermelons splash through the crowd. A couple cantaloupes went flying in "Creeping Death." Apples were brought out for "Last Caress." There was even a giant gourd at one point, which actually made for a better phallic joke than splattering substance. The biggest hit of the night, though -- which was a first for the band -- was a fun-pack of chocolate-pudding cups for "Fade to Black." Brown is a color you don't want to see splattered on the floors and walls of a rock club.

Oh, yeah, I almost forgot the jokes. Brent Hedke, the Gallagher of the band, half-heartedly told bits between songs: "What's the deal with scented toilet paper ..."Sperm banks are never gonna work ..."

Talking with Hedke the next day, I was shocked and awed to learn that those routines were the actual work of the real Gallagher.

"I'm convinced he's the least funny human being to ever walk the Earth," Hedke said.

Of course, that only reinforces the most obvious question for Hedke: "How on Earth did you come up with this?"

He thought it up in the drunk tank (i.e., not Earth) after being arrested for running down the street in a jock strap with a couple of other guys. Guitarist Peter St. Martin corroborates the story but says the idea didn't seem so crazy when he later heard it.

"Dread Zeppelin makes a lot of money covering another band in really, really stupid ways," said St. Martin, who, like the rest of the 20-somethings in the group, sees Metallica as their Zeppelin. "They're the one band we all learned to play our instruments to."

Instead of rehearsing the songs, then, the hardest part about getting Metallagher off the ground was finding that perfect rainbow shirt. Second guitarist Jason Torkelson finally discovered it at a thrift store for $1 a week before their first show. Since then, their main challenge has been convincing club owners to book them.

"We do help clean up," Hedke said.

The band knows its biggest dilemma is yet to come: if (or when?) a lawyer from Metallica or Gallagher calls up and threatens to sue over copyrights. If the Olympic Hopefuls can get sued by the Olympics ...

"Hopefully, as long as we don't record or don't make more than a couple hundred bucks a night, they'll leave us alone," Hedke said.