Penn and Teller: Back and in the Chips : Theater: The Bad Boys of Magic return to the Southland, performing tonight at UC Irvine and Friday at UCLA.

A grand variety of acts may have performed in Southern California in the last few years, but one thing that has yet to grace any stage is a gas-powered, deafening chipper-shredder. Penn and Teller aim to remedy that cultural lack.

“A few years ago I bought a chipper-shredder to turn my useless yard rubbish into useful mulch,” the mono-monikered Teller explained. “And we were impressed by the extreme power and terror of the chipper-shredder. Over the last year we’ve devised a vanishing bunny rabbit trick, utilizing the chipper-shredder. You can sort of put it together yourself from there.”

Teller (who legally dropped his first name after years of no one using it) is the duo’s smaller member, eerily silent onstage. He says the silence comes in handy when he’s drowning or swinging upside down over a bear trap. The physically and verbally imposing 6-foot-6 Penn Jillette, meanwhile, embellishes their bold comedic magic with monologues of Spectorian density.

The Bad Boys of Magic, who perform tonight at UC Irvine’s Bren Events Center and Friday at UCLA’s Wadsworth Theater, describe themselves as “sub-stars”: “If you spent 20 minutes recounting to the average person everything we’ve done, chances are he’ll eventually go, ‘Oh, them,’ ” says Penn.

In their 18 years together, Penn and Teller have created a wealth of unique reference points. They’ve irked some magicians by breaking the rule of revealing how their tricks are done, but the tricks remain twistedly wondrous nonetheless, such as ones where Teller is seemingly impaled by power drills. They do card tricks in which the key card turns up in the mouth of a rat balanced on Teller’s nose. They’ll pull a rabbit from a hat on David Letterman’s show, followed by 500 cockroaches.

Oh, them.

The performances this week are among a handful they are doing to break in new material. The chipper-shredder bit is one of four new routines that will be accounting for a quarter of the two-hour show. They intend to return to the Southland in a year or so with an entirely new show celebrating their 20th year of performing together.

When they met in 1974, Teller was a Latin professor who dabbled in magic, and Penn an unemployed clown-school graduate. Neither harbored dreams of stardom. Instead they were drawn to their present pursuits through an annoyance that no one was practicing magic with the attitude and intelligence they felt it deserved.

Penn said, “When Teller and I first met we began having late-night conversations about the intellectual implications of magic, if you will, the fact that it’s built on irony, that things appear one way and are really another, and that its subtext is all swindling. Although everybody is talking about ‘willing suspension of disbelief’ in magic, it has nothing to do with that. In fact one of the definitions of magic could be unwilling suspension of disbelief.”

For all the noisy magic of their shows, Teller has a surprising notion of what audiences appreciate about them.

“I think people value the partnership they see. They see onstage two people who could not be less like one another. They routinely put their lives into the other person’s hands. The division of labor in our act is one I haven’t seen any other place. Pretty much if there’s a physical stunt to do I do it. Pretty much if there’s a word to speak, Penn does it. That’s a kind of dependency that seems to me to be extremely uncommon.”

They are, Teller says, “two guys who like to learn things and like to have adventures. In a lot of ways, I think we live our lives more like fictional characters from the kind of book you read when you’re 12 years old than we do from proper grown-up values. So it strikes me as strange, and great, that as many people as seem to like us do.”