Charleston’s Gangrene Machine is an oddball quintet of intellectual punks with the dynamic clamor of a Frank Zappa ensemble and the solemnity of an obscure Monty Python skit. Their show is a parade of unorthodoxy in full costume, an approach that might have straight-laced spectators asking, “Why?” — to which the band would respond with a cavalier shrug of “Why not?”

Their overt technical skill takes them in any and all directions, sometimes simultaneously. Initially, they seem to be experimental funk. Then they’re thrashing and angst-ridden. Once you think you have them pinned down, they’re playing Primus-like funk-punk with a distortion that makes you feel like you’re at an extraterrestrial circus.

Gangrene Machine’s unique style has landed them a show at the Pour House this week — a feat that came as a surprise to nobody but them.

“I thought it was just going to be a couple guys jamming in a storage shed,” says bassist Eliott Vanotti. “I never thought we’d be headlining at the Pour House. I didn’t think that was something local bands did right when they first started playing.”

Gangrene’s first practice took place last year on the day after they met each other at a party held by drummer Dylan Ray. They decided the sound was too good to ignore. A few months later, Trey Cooper joined in as the keys player. “Thank God,” Vanotti says. “He’s a prodigy.”

Cooper no doubt brought the funk. With him, Gangrene’s scope of musicality has risen to a new level. “There’s a lot more depth to our music now, and there’s a lot of different things you can listen for. I like that,” Vanotti says.

Not long after forming, the group experienced their first rock star moment at a live show when a pack of screaming girls gathered at the stage and demanded to hear the band’s call-and-response party anthem, “Purple Drink.”

“It is pretty catchy,” Vanotti says. There’s no doubt about that. The lyrics consist of a whopping six words, tightly phrased in a way that you can’t help singing along with lead vocalist Matt Dobie, “Give me that purple drink, yeah!”

That’s one way to get a crowd involved, but Vanotti and his mates have something else in mind for this week’s Pour House show. The first 30 people in the door will receive raffle tickets, and, at mid-set, one of them will win a bizarre door prize specially selected by the band.

“You never know what you’ll win, but it’s going to be a good one, I can tell you that,” Vanotti says. The band presented their last raffle winner with a ’70s porn film on an 8mm film reel. “I literally have a suitcase full of these old pornos that I can’t watch. It’s so sad. I bought it off a homeless guy once for like three bucks.”

Vanotti’s latest thrift purchase was a $10 clown suit from Goodwill, a costume he can’t describe without laughing.

“It’s just such a ridiculous-looking clown suit,” he says. It wouldn’t be a surprise if he sported it on stage. He’s performed twice in adult diapers, once in a floor-length kimono, and another time as a sombrero-wearing taco. “It’s fun. People go to shows to be entertained, so that’s part of it.”

With Halloween coming up, he hopes, or maybe demands, the rest of his band will join him in costume. “If they don’t, I’ll kick their asses,” he laughs.

Although their lashing jams and shouty vocals may have you thinking otherwise, the Gangrene guys are hardly typical tormented souls. Vanotti says it’s all part of the elaborate act.

Lead singer Dobie often peers around at the crowd as he sings and usually breaks free to dance like a leprechaun. It’s a dramatic incongruence that reminds the audience that nothing is sacred.

“It’s not like I’m trying to play a concerto with my diaper on,” Vanotti says. “We try to make it crazy, and yeah, we’re a little in your face about it, but in a funny way. I guess we like to pay homage to Frank Zappa like that.”

For some in the local scene, it may be a breath of fresh air to see a punkish rock band that doesn’t simply swat blindly at aggression and intensity. Gangrene Machine aims for more than a tight set of heavy grooves and rhythms, and they do it with humor, a dash of funk, and a bit of unexpected catchiness.

So are they headed for rock stardom? Vanotti leisurely dismisses the topic. “I don’t know. Maybe everybody dies in a plane crash. Maybe that’s the end of the band. Who knows?”

Let’s hope they deliver a few more purple drinks before then.