That's for sure. The other sculpture in Mueck's two-work New York gallery debut is just as well made but less startling, and points to a weakness in his work. Mask II is an enormously enlarged portrait head of the artist asleep, in which every hair of the head, eyebrows and beard has been individually fashioned, then inserted into its own hole. Mostly, however, this hollowed-out head looks like a carnival prop.

I'm not even sure that what the 43-year-old Mueck makes is art. I am sure that his ultrarealism produces staggering hits of wowie-zowieness. A couple of seasons ago, his Dead Dad -- a small-scale, naked, dead male -- wowed crowds at the "Sensation" show. His oversized, naked, cowering man is currently stopping people in their tracks at the Hirshhorn. Whether you think of his sculptures as supermannequins, anatomical models, Madame Tussaud figures or rote realism, Mueck is his generation's winner of every verisimilitude award in the book -- from Best Varicose Veins Painted Under the Skin to Best Foreskin and Labia Majora.

Some think this verisimilitude adds up to a lot. Newsweek critic Peter Plagens lauded Mueck as "the best thing to happen to figurative sculpture in ... generations." Topping that, a cover story for Modern Painters raved that Mueck was "the equal of Vermeer." Others aren't as enamored. Critics have branded him "a one-hit wonder" or snobbishly dismissed him as a "model maker." One naysayer told me, "He's a phenomenon that should be cut off at the knees." Another decried his work as "a cheap shot." But is Mueck that different from his British cohorts who also deal with hyperrealism?

Although he was in "Sensation," Mueck is not entirely of it. Born in Australia in 1958, he has lived in the U.K. for the last 20 years but didn't come up through the same channels as the other YBAs. Self-taught, he worked for two decades in children's television, animatronics, and the movie industry before making his first work of art in 1996. Nonetheless, he falls within the parameters of the YBA aesthetic, which -- if reduced to its simplest component -- is realism; some might say, realism with a vengeance. From Damien Hirst's dead animals and Rachel Whiteread's casts of everyday objects to Richard Billingham's photos of his family and Tracey Emin's life as art, British artists are obsessed with realism.

So is their public. Maybe it's a cover for the legendary English distrust of visual art, a puritanism born of disdain for pleasure, or a genetic aversion to ambiguity. Whatever it is, the one thing most recent British art isn't is ambiguous. It cuts to the chase, goes for the throat, appeals directly to the audience, and shocks the fear of art away. Even though there may be nothing more flavorless or enervating than sheer mimicry, for better and for worse, realism is what this generation of British artists excels at.

Mueck's sculpture is the most mimetic of them all. His shifts in scale alter our perceptions and rattle our radar; his skill is exemplary. But as anatomically and dermatologically correct as they are, after the zap of the initial encounter -- which is jolting, and nothing to scoff at -- Mueck's sculptures produce very little internal tension. Rather, they suspend you in a soothing present, a visual feedback loop where you experience the pleasure of noticing -- noticing how Mueck put this detail, that hair, this freckle, wrinkle or pockmark where it is. They induce a kind of narcissistic reverie, surprising us with how long and how intently we can look at what we look like.

Although he's bound to retain his "Most Real" titles for some time, the problem with Mueck's hyperrealism may be the problem with hyperrealism in general: Sooner or later someone will come along and find a way to make it more real -- get blood to circulate below the skin, make androids dream of electric sheep. Duane Hanson's best figures work because they're so real they're fake; they blend in and make mystery. Many of Charles Ray's sculptures work because they're so fake they're real; they stand out and change perceptions. Mueck wants his art to play in the zone between the two; he wants to make things real and unreal at the same time. Mother and Child, a conventional yet sensational subject realized on a beguiling scale, flirts with that zone, occasionally touching it. In spite of the wonder of gazing at someone asleep, the clunky divertissement of Mask II is all zap and no play.