“I came to magic absolutely hating magic on a very, very deep level,” says Penn Jillette.

“Modern American magic, late 20th century magic, is tremendously disrespectful of the audience,” he says. “Jerry Seinfeld describes every magic act as ‘Here’s a quarter, now it’s gone, you’re a jerk. Now it’s back, you’re an asshole, show’s over.’ That’s really accurate. So magicians did not in any way speak to people. And Teller and I really didn’t want that. We hated that.”

So Penn & Teller decided to reveal how some of the popular illusions are done: “Not so much to give away the secrets, not for prurient reasons, not for the shock value, but as a peace offering.”

That didn’t always endear them into their fellow magicians at the time, but almost four decades into their career as a team, their combination of ingenuity and skepticism has made them some of the most popular magicians of their generation. They’ve done TV, Broadway and when they finish their just-inked contract to play the Rio in Las Vegas, they’ll break the record for longest continuous run for a headline artist at a single Vegas venue.

The pair were introduced by musician Weir Chrisemer. Recalls Teller: “He staged Khachaturian’s Sabre Dance, with some crazy guy on a unicycle, wearing a checkered table cloth as a cape, juggling, and that person was Penn.”

Chrisemer, Penn and Teller were soon performing together at San Fran’s Asparagus Valley Cultural Society. Penn was 18 and a veteran performer, Teller a 25-year-old Greek and Latin teacher. “Penn’s very at the time raucous rock ’n’ roll sensibility was very distant from mine,” says Teller. “I was a classics major in college and had studied harpsichord and music theory and all that sort of old-fashioned civilized stuff, and Penn was a rock ’n’ roll, circus nut.”

But Penn thinks that contrast, and their stage personas, made their act more interesting. “Art thrives on its limitations and having to work with Teller being silent gave us a lot of interesting stuff.”

In the early days, they fought constantly over the act, says Teller. “I was pulling in the direction of classical theatrical things, and Penn was pulling in the direction of wild and really rock ’n’ roll things. And all of these were wrapped around magic, juggling and music.” And they still speak “bluntly” to each other in rehearsal about artistic disagreements, “although over the years we’ve learned a lot from each other.”

Teller sees those offstage conflicts as a source of conflict and tension in the act. But onstage, the duo is unusual for its lack of conflict. Penn says most comedy teams let the audience eavesdrop on their argument, but with Penn & Teller “the conflict is with an idea or the world or an audience or the stage.” As a result, Penn calls their act “a one-character show done by two people,” and Teller says within that character, “it became as though Penn was the voice and I was the action.”

They may still be arguing in rehearsals, but they’re still creating new illusions. Teller feels that’s a key to their longevity.

“Other shows in Vegas run the same show until they’re blue in the face and die,” he says. “We have three new things in the pipeline, on the way to being onstage right now. One of them will manifest itself in about two months, one in four or maybe five months and one a little later in the year. And as we create these new things, we rotate them into our show pull out something that’s been in there for a long time that can take a break. That’s great fun, the vitality of always having something new that you’re working on while every night doing something you love.”