A little naked man, maybe three-feet tall, sits cross-legged on the table. Behind him looms the gangling six-foot three frame of sculptor Ron Mueck himself. Further back against the window, staring out over all of us, is an eight-foot adolescent girl.
It is the same disturbing double-take that visitors experienced at the Royal Academy's Sensation exhibition last year when they first stumbled across Ron Mueck's moving sculpture Dead Dad - a naked male figure laid out on the floor as if on a mortician's slab, perfect in every detail from the yellowing calloused soles of his feet to the stubble on his pallid grey face; hyper-realistic but reduced to childlike proportions as if to emphasise how death strips us bare and diminishes us.
"I was going to make it life-size originally, but it would be too much like a special-effects dummy in a horror film," Mueck says. "I blocked it out this size and immediately thought this is perfect - you could cradle this," he adds, hugging the air gently in his arms.
Mueck made Dead Dad to help him come to terms with missing his own father's death. "He died in Australia, and I never saw the body," Mueck explains. "This was a way of saying goodbye to him and creating something to fill the space of that empty experience."
The sad serenity of the finished piece stands in contrast to the violence of the original scene. "He died vomiting. My brother was trying to resuscitate him and it was messy, just horrible," says Mueck. "That was the last picture I had in my mind. If I'd been there I would have cleaned him up and laid him out, and that's what I wanted to see."
Is it hard to have such an intimate object on display, being pored over by members of the public? Or indeed to sell it to Charles Saatchi, who owns nearly all of Mueck's output? "The process of making it is where I went through all that emotional stuff," says Mueck, "spending time imagining what his hands or face must look like. By the time I'd plugged all the hairs in, it had started to become a lump of silicone."
Dead Dad was only the second sculpture Mueck had exhibited, but it immediately touched a nerve. It has elicited piles of fan mail, and within weeks of it going on show I was hearing poems written about it. Now he is frantically putting the finishing touches to his first solo show, opening this week at the Anthony d'Offay Gallery.
Surrounded by a small heap of loose eyeballs and discarded pink toe moulds, Mueck delicately peels off a transparent plasticky flake, like an uncooked prawn cracker; examines it carefully; eases back the cuticles on his subject's outstretched foot; considers a moment; then rejects the nail wordlessly, suspending his pedicure. Mueck has high standards in toenails. This one has not met the grade.
Such attention to detail makes each sculpture a laborious process. Ghost, the gawky young giantess leaning against the window, has taken the best part of three months. Starting with a clay sculpt, layers of pre-coloured silicone are painted, layer by layer, on to a plaster mould. The limbs are reassembled and stuffed with foam and a wire armature. Then the detailing begins.
Ghost-girl begs not to be looked at. Sure she looks awful. Wishes she could hide. A glint of sunlight catches her pale, awkwardly turned face, revealing soft, downy wisps above the corners of her jutting bitten lip, the pink-edged mousiness of her uncertain eyes, a speckling of blotches by the navy strap of her baggy school-issue swimming costume. Had Mueck not allowed her to shave her legs, she would have taken a year. "Unfortunately humans are hairy all over," sighs Mueck. "At a certain point I have to say enough."
The moody little downcast chap cross-legged on the table pathetically tries to cover himself with a child's pale-blue cardigan. Unfortunately for Mueck, the cardigan covers little, which means endless trips to the hair cupboard at the back of the studio.
"The first models I made were done using my own hair," he says, returning with a fistful of dark strands. "I used to cut bits of hair off my legs and punch them in, but I started looking very blotchy."
Reaching under the cardigan, Mueck disconsolately fiddles with brooding- man's head. "It would probably help if I was a better hairdresser - it probably looks like they cut their own hair," he says. "I cut mine - shear it," he adds, looking sheepishly up towards the haphazard tufts which ruffle above his huge furrowed face.
"I like to be in control of everything," he admits.
It was this obsessive perfectionism which two years ago finally led Mueck, now 39, to give up his lucrative day-job making models for film and advertising.
After a few years of window-dressing and a stint in children's television back home in Melbourne, Mueck learnt his craft over many years with Jim Henson's Muppet empire, making griffins on Dreamchild and goblins for Labyrinth. Relics of his subsequent advertising career litter every nook of his studio: a giant rubber dragon-skin from a crispy snacks ad, a flock of sheep's heads from a Smirnoff campaign, a furious Schweppes-drinking colonel, morsels of waterskiing Kit-Kat sheepdog.
His children miss seeing dad's work up on billboards across town, but Mueck feels a free man. "Everything I was doing was geared towards that final flat image, the piece of print," he explains. "It felt like I was just a step in the process, a tradesman doing one portion of the finished thing. Everything was predetermined. I was always telling someone else's story, really. I wanted to make something that a photograph wouldn't do justice to."
His chance came when his mother-in-law, the painter Paula Rego, invited him to make a Pinocchio figure for her to draw from. "She said put something of yourself into it, as you were when you were eight or nine," remembers Mueck. "I finished it, and she said, 'This is modern art, isn't it?'," he chuckles.
Rego decided to include the piece in her sequence at the Hayward Gallery's 1995 "Spellbound" exhibition. So eerily lifelike was the quizzical little figure that a gallery security guard used to turn the boy to face the wall every night.
The halls of the Saatchi collections may be peppered with human figures nowadays, from Chapman brothers' mannequins to Gavin Turk's Pop or Abigail Lane's Misfit, but Mueck's characters have deeper tales to tell.
"I love looking at people on the Tube tying to guess what their story is," Mueck admits. "I was really self-conscious as a teenager - terribly shy - I wanted to be invisible. I wasn't very sociable, and I'd just stare at the other groups of kids, unable to imagine what they might be talking about."
Mueck turns to add a dab of face powder to a silicone seam. "Although I spend a lot of time on the surface," he says, "it's the life inside I want to capture."
Ron Mueck sculptures, Anthony d'Offay Gallery, Dering Street, London W1 (0171-499 4100), to 18 June