They are like an entire animation studio crammed into two wiry bodies.

They are the Umbilical Brothers, who bring their production “Thwak” to the Maine Center for the Arts in Orono at 8 p.m. Saturday.

What is “Thwak”? The Aussie duo, David Collins and Shane Dundas, struggle to describe it in a recent phone interview from New York.

“It’s a little bit of insanity brought to life,” offered Collins, the one with the long curly hair.

Tut-tutting that explanation, Dundas added, “It is what it is. It’s a human cartoon, like a kids’ show for adults.”

Well, that makes it clear as mud. What Collins and Dundas do is combine mime, improv and a boatload of sound effects into a frenetic 85 minutes of physical comic fun.

“We’re like a pop-culture sponge, and we’re squeezing ourselves out on the audience every night,” Collins said.

The pair come up with the ideas for their theater shows, which also include “Two Coats and a Hatstand From Hell,” “Don’t Explain” and “Heaven by Storm,” by writing down bits as they pop forth from their subconscious minds.

“Our productions come out of our goofing off,” said Dundas, the one with shorter hair. “A lot of ideas are involved in our shows. It’s a comedy stream of consciousness.”

The Umbilical Brothers have been performing “Thwak” since 1999. Still, every night, the show is a little different.

“We fool around within the structure of the show,” Dundas said. “We dedicate pockets of time to improv.”

“Oh, that make sense,” Collin rebutted. “Planned time for improv.”

These soul brothers have been together since 1988, when they met at the University of Western Sydney. They knew they had a winning combination on the day that Collins broke Dundas’ nose.

“We were in a jazz dance class,” Dundas recalled. “The teacher told us to get a partner, then do what we wanted for the middle eight measures. We decided to do a Jackie Chan fight scene. David got a little too close.”

“I don’t know what he’s complaining about,” Collins rejoined. “We still passed.”

They started as a change-of-pace act in comedy clubs, then went on to win the Australian edition of “Star Search.” They’ve gone on to tour around the world, both in countries that speak some version of the queen’s English and those that don’t.

“It’s a universal language,” Collins said. “There’s a lot of cartoons and pop-culture references, which everyone seems to get.”

“Everybody’s usually on board by the 4-, 41/2-minute mark,” Dundas added.

The high and low points of their career happened on the same weekend, when they performed at Woodstock ’99. Following James Brown, they killed on the A stage. Then they moved to the B stage, and almost got killed, playing in front of a group of incensed hard-rock fans.

“If you look at the tape, you can very clearly see them saying, ‘You suck!’ among other things,” Dundas said.

Another highlight was performing at Jerry Seinfeld’s 40th-birthday party.

“We’re not sure if we were performing for any guests,” Collins said. “It may have been just the catering crew.”

Very young children can enjoy the talents of the duo on the Nickelodeon show “Maisy,” for which they supply all the voices and sound effects. They plan to bring their latest production, “Speedmouse,” to New York in the fall.

They’re often referred to as an act that appeals to those from adolescent age on up through adulthood, a phase the Umbilical Brothers are actively resisting.

“We’re kind of like ‘The Simpsons,'” Collins said. “The kids can enjoy the color and the movement, but the grownups will get more out of it.”

For tickets, call the Maine Center for the Arts box office at 581-1755. Dale McGarrigle can be reached at 990-8028 or dmcgarrigle@bangordailynews.net.