"I don't want you to leave tonight thinking about how we do it," says the illusionist Penn Jillette, in between gulps of fire, "but why." That's easier said than done. When you see a man swallow 100 separate needles and a ball of thread, then regurgitate 100 perfectly threaded needles, "why?" must take its place in the queue behind "how on earth?"
Sometimes, Penn and Teller tell us. The Las Vegas-based double act are paid-up demystifiers, dedicated to exposing all the usual explanations for effective magic. Body language is bunk, there is no power of suggestion, and "all supernatural events are bullshit". What's happening is concealment and misdirection, as Teller demonstrates with a neat routine involving a vanishing cigarette, which he first performs, then flips around to reveal its artifice to the crowd.
There are also plenty of tricks that go unexplained. How, for example, does Teller survive for 10 minutes in the "underwater coffin of certain doom"? This is the duo's first UK appearance for 16 years, and theirs is a very enjoyable variety show, in which magic tricks alternate with demonstrations of technique, dramatic vignettes, and a knife-throwing skit in which one blindfolded volunteer is ruthlessly duped for the audience's entertainment.
The gasp factor isn't as high as in, say, Derren Brown's recent work, in which even Brown's mistakes are revealed as part of some all-knowing masterplan. Here, a malfunctioning levitation routine is just glossed over. No matter: there are enough successful, unfathomable tricks to go round, and the pair (one fairground barker, one silent clown) are open and convivial hosts. Why they do it, who knows? But while they're doing it, they're well worth seeing.
