THE TURTLES.

Zhang Xin likes to talk about her fascination with left-wing British intellectuals during her years at Sussex and Cambridge. Pan Shiyi, her husband, is a believer in Taoism who describes himself as a "feudal" Gansu country boy. When you see them on television and in magazines, they are often dressed in a kind of Shanghai-Tang chic: Pan, with his black-framed techno glasses, might be wearing a silk brocade jacket; Zhang, with a dyed streak of ash-blond hair right above the eyes, might have on a sleeveless linen top with a mandarin collar and butterfly buttons. They look like art dealers or film producers. In fact, they build apartment complexes, office towers, and shopping plazas. At the ages of thirty-nine and forty-one, respectively, Zhang and Pan are the co-C.E.O.s of the Beijing-based firm soho China, and the most visible real-estate developers in the country.

On a cold spring day last year, Pan and Zhang hosted a gala to celebrate the opening of their latest project, Jianwai soho, twelve white minimalist high-rises arranged in a tilted phalanx on a prime block of Changan Avenue, Beijing's main boulevard. Despite persistent drizzle, hundreds of luminaries showed up: businessmen and government officials, architects, publishers, artists, fashion editors, actors. A sudden downpour turned the open-air ribbon-cutting ceremony into a brave dash through the rain, spoiling starched clothing and fancy hairdos; at the formal dinner for five hundred guests in a gigantic white tent, some people were shivering in the evening chill. But glamour prevailed, as models sauntered down an improvised catwalk wearing Bulgari jewelry and Valentino couture. Later, a pair of professional dancers from South America performed a tango. The hosts worked the floor separately. They stepped onto the dais together only once. Pan, in a dark Prada suit, thanked the guests in Chinese. Zhang, in sky-blue silk embroidered with yellow dragons, offered appreciative remarks in English for the benefit of the many international guests.

The evening reminded me of a similar occasion, two years earlier, celebrating the completion of Architectural Gallery, at the foot of the Great Wall, a pet project of Pan and Zhang's. The gallery featured twelve fanciful houses, each designed by a prominent Asian architect. One, by Shigeru Ban, was a house made of laminated bamboo. Another, designed by Yung Ho Chang, a Beijing architect who was trained in California, was built entirely of packed earth. Each of the twelve houses was priced at a million dollars, which, even for Beijing's newly rich, was a daunting sum to spend on a weekend residence that was more of a designer's conceit than an example of luxury living. The project has since been renamed the Commune by the Great Wall and, partly because of the publicity it generated, has done well as a convention center and tourist attraction.

Jianwai soho is far larger in scale: when everything is completed, there will be twenty high-rise towers and four villas, encompassing seven hundred thousand square metres, and its projected sale value is about $1.2 billion. The price per square metre, at about two thousand dollars, is high but not beyond the reach of the intended clientele, who have been drawn by the buildings' style, a contemporary blend of concrete, steel, and glass with interiors of fine-finish woodwork. By the time of the gala, eighty per cent of the units had been sold.

The gala wasn't the only promotional event Zhang and Pan had arranged for the complex. Earlier that afternoon, in a conference hall inside one of Jianwai soho's buildings, they presided over a forum called "A Dialogue Among Architects: China and the World." Besides Riken Yamamoto, the Japanese architect who designed Jianwai soho, the most prominently featured speaker was Patrick Schumacher, the partner of the celebrated Baghdad-born architect Zaha Hadid, who was then designing another project of Pan and Zhang's: an upscale apartment complex on Changan Avenue near Jianwai soho. Schumacher showed slides and spoke to a packed hall, with Zhang standing nearby to translate for him. On a screen behind him, a cluster of buildings shimmered, their color somewhere between silver and gold. I have heard the Hadid design described as a "school of fish."

The image that often arises when people speak of Pan and Zhang is that of a pair of turtles. In China, people like Zhang, who have spent time in the West, are known as hai gui--a pun on "sea turtle" and "returnee from the sea." As the Chinese economy has become more integrated into the global market, hai gui have grown numerous. ("Globalization means going home," one hai gui said to me.) By contrast, people like Pan are represented by tu bie, the local turtles. The hai gui are valued for their international perspective; the tu bie are the ones who know how to get things done. Pan and Zhang have become the best-known tu bie-hai gui team in China. But, as they've learned, the alliance between tu bie and hai gui isn't always without friction.

China has been called the world's biggest construction site; everywhere you turn in cities like Beijing, there are cranes, scaffolds, steel rebars, skeletons of old buildings, half-finished new ones. Yet the people who are directly responsible for this constant din have largely stayed out of the public eye, and not without reason. Developers are regarded as China's robber barons, men who have taken advantage of the muddled transition to capitalism by means of guanxi (connections), bribery, and fraud.