Perfect ghosts in perfect machines

The two women are beautiful and utterly composed, their couture dresses fall smoothly towards slim ankles and high heels. Beyond and far below them, through the picture window that hangs as if in a stage-lit void, the distant street lights and traffic of Los Angeles spread out in a grid of fire dissolving into the smoggy dusk. Outside, in the shadows, a man stands quietly, looking in, waiting for his moment.

The two women are beautiful and utterly composed, their couture dresses fall smoothly towards slim ankles and high heels. Beyond and far below them, through the picture window that hangs as if in a stage-lit void, the distant street lights and traffic of Los Angeles spread out in a grid of fire dissolving into the smoggy dusk. Outside, in the shadows, a man stands quietly, looking in, waiting for his moment.

Just out of shot, two tanned men discuss missile shares. When they talk their lips hardly move. Their foreheads are smooth because they've never frowned. "Carmel has some good points," says one in a monotone. "Do you mean the place or our cook?" says the other, deadpan. They hardly notice the room they're in. They take it for granted because one of them paid for it, cash, wads of fifties handed to some big-deal intellectual architect called Pierre Koenig. And the men are thinking: the gals look good enough to eat, with a squib of Mort's Red Dog barbecue sauce, right here and right now in this dream home on the edge of JFK's New Frontier in 1960.

Outside, in the night, the stranger's thumb tightens over the button. His name is Julius Shulman and he's not particularly interested in the women.

He's here for the wafer-thin roof and the exposed steel girder that carries it; he wants to get to the truth of the raw rectilinear concrete balcony supports and the minimalised detail.

Shulman's thumb pushes down and there's an articulated "stritch" as the camera's shutter falls. And he has what he wants - the hardcore soul of the architecture, sealed in a moment in time, as radiantly delineated as a body in a block of ice. But, no. It didn't happen quite like that. The women were models. There were no knuckle-jawed lunks standing at the bar. And the women had been sitting in darkness until Shulman was ready to bathe them in synchronised floodlights. "Okay, girls, start looking natural."

Natural? However composed, the weirdness remains. Shulman's scintillating images lure the image tourist into narratives, and they make a big point about buildings, whispering the insidious question that applies to all architecture: is this building suitable for human beings? Or, conversely: what have flesh and blood and emotion to do with this or that space?

Shulman's most rivetting images begin in 1947 with Richard Neutra's Kaufmann House in Palm Springs, an almost completely horizontal essay in stone, steel and glass, set against a lion's pelt of scorched hills.

Its bedroom is a steel-framed box, glazed on two sides and in it a woman in an ochre blouse sits at a writing-desk. The house is precise; she is precise. And is everything else in the Kaufmann House precise? Is it hard to be imprecise in such a home - or does certain architecture necessarily provoke strange behaviour?

This combination of precision, brute landscape and carefully arranged people is typical of Shulman's search for meaning. But what a bizarre perfection.

Take the monochrome shot of the Shangri-La apartments in Santa Monica in 1940. A woman sits in the lobby, looking down at a leatherette-bound cocktail list. Her mouth is set because she is concentrating on relaxing.

And then, as they invariably seem to with Shulman's images, the alternative narratives begin to barge in like Raymond Chandler's Moose Molloy in search of his Velma. Damn, maybe that's Velma in the shot.

Could I step into the frame and make something happen - ask her what she thinks of the building's design, perhaps? But what if she just said: "Huh?"

In this narrative trip-wire sense, two of Shulman's images are irresistible. In the interior shot of Case Study House 21, taken in 1958, the shifty intruder finds a young couple "at ease" in a typically steely Koenig living room; she sits in the foreground on an angular black leather sofa. Her ashen face is framed in ruches of auburn hair. She wears a powder-blue dress that looks like something soft that would undulate on coral.

The watcher's eye flicks from the couple to the architectural details. What have those steel I-beams to do with the knot of his tie, or her thick eyebrows? What "natural" thing can happen next in such precisely unnatural surroundings?

The second image - from the Bass House, taken in 1958 - shows a woman stranding gracefully in an ultra-modern kitchen. Light falls on her flawless forehead, her pearly bottom lip, her neck. She is sheathed in an off-white outfit - a little number from Schiaparelli, maybe. She holds a paring-knife carefully against the skin of an orange. Four cobs of corn and a squash lie on the worktop. They look unreal because they are natural. And what is this Grace Kelly of the cuisinier thinking? Is she worried that her husband will discover Benton Snyder's charred body in the arroyo at Black Rock Junction?

Shulman's provocative images deliver architecture with a brilliantly astigmatic artifice - one artifice prisming into others. The images are ironic and cunning, the Stepford husbands and wives used to humanise architecture that, in its time, might have been thought by Joe Dokes (US Mr Average) to be whacko.

But Shulman draws the eye in inexorably, the gaze skewered by needle-sharp details of architecture in the Twilight Zone. When you look at images like these you wonder if a visit to the the buildings themselves might spoil things.

Julius Shulman talks at the RIBA, London, on 7 November (020-7307 3699). His 'Modernism Rediscovered' is published by Taschen