Yesterday the world watched the opening ceremony of the Beijing Olympics. Athletes filed past the cameras hoping that the next time the flashbulbs pop, they will be on the podium.

But there’s one star you will definitely see on your screens this summer, and from within it sweating, shaking sportsmen and women will be beamed – beaming, weeping or both – across the world. It’s CCTV, the new headquarters for China’s state television organisation. The second largest office building in the world, second only to the Pentagon, it has been designed by Rem Koolhaas and it is unlike any other building you’ve ever seen.

It has a hole in it, almost 200 metres wide, around which its gawky limbs contort themselves in a huge angular loop. Each titanic limb tilts away or towards the next, like an Escher painting, culminating in a gravity-defying zenith in which the two come together in a jaw-dropping, “look-no-hands” cantilevered corner, jutting out over the city.

You may not like it. Its Orwellian looks and, indeed, function mean that this is no easy building to love. But you can’t deny its power. This is one of those moments when you know an entire culture is morphing into something else, something new. The genie is out of the bottle. Architecture will not be the same again, and nor will China. CCTV is the most significant building of the 21st century yet.

Its German co-architect, Ole Scheeren, looks every inch the master builder. Tall, dark, handsome, sharply dressed and dating China’s biggest movie star, Maggie Cheung, Scheeren is king of Beijing. “We could have gone the easy route,” he says, “and built much taller like the others that bid for the job. But that’s just not interesting, is it?” What was interesting was getting out of the “my one’s bigger than your one” race for the skies and “creating a new type of skyscraper”, one in which intelligence mattered. CCTV is a paltry 234 metres (768ft).

When Scheeren visited the site six years ago the neighbourhood was empty. “Beijing city planners showed us an image of what would be Beijing’s new central business district, with a forest of 300 skyscrapers.” They’ve already arrived: phallic, boring. “So faced with this, a question emerged. This year Asia has more skyscrapers than the West. A typology invented in New York and Chicago 100 years earlier has been adopted more successfully in Asia as a triumphant symbol of its own modernisation. So what could an Asian or a Chinese skyscraper become?”

Voilà. When an architect claims to be reinventing anything, reach for a pinch of salt. But Scheeren’s firm, the Office for Metropolitan Architecture – founded by Koolhaas – is true to its word. One of Koolhaas’s bêtes noires is architectural icons. He despises their “vulgar desire to impose flashy new form”. He prefers what he calls “antiicons”, like his Casa da Musica in Porto, Portugal, whose awkward form both repels the tourist’s camera and attracts it.

CCTV does the same. Yes, its odd looks are pointedly chosen to stick out against its predictable neighbours, “But this is both an icon and a nonicon,” Scheeren says. “Icons have a singular appearance. Look at them once and that’s it. Traditional Chinese architecture, though, is something you cannot simply comprehend with a glimpse, you have to let the space unfold.” CCTV works similarly – like a giant piece of Chinese calligraphy, a single image made up of symbolically loaded parts. Move round the building “and it unfolds, changes configuration. It has depth.” More importantly, he adds, its iconoclastic shape came not from wilfulness, but from the building’s function – a public building on the world stage for an organisation renowned, rightly or wrongly, as chief propagandist for a one-party state.

Like most things in China, the media are changing at a frightening speed – in May the Government allowed CCTV and foreign journalists unprecedented access to the Sichuan earthquake disaster zone. CCTV itself is metamorphosing. “The group running this project is young,” Scheeren says, “mid-thirties to mid-for-ties, well-educated, exposed to the West. It sees itself in a much more responsible, global context. The BBC is one of their role models. They talked about making part of CCTV a more free enterprise. This seemed encouraging, and to try to support it, worthwhile.”

It goes for China as a whole, he says – “Yes, it has many problems, but you either choose to change that, or you isolate yourself. Once you experience China, nothing’s so black and white.” So, like the Olympic Stadium’s architects Herzog & De Meuron before him, Scheeren excuses his engagement with a country vilified for its human rights record, by his faith in transforming it. CCTV though, already embedded in the city, and housing the state’s main tool of propaganda stands, I think, a greater chance of doing so than HdM’s isolated “Bird’s Nest”.

Either way, Scheeren has been adamant about workers’ conditions on site: “We’ve had no casualties here. We were very explicit in all our intentions from the beginning,” he says. “This was to be an exemplar. And we said let’s create “public space” in the building, make it the most transparent TV station in the world.” Such words, innocent here in the West, are dynamite in China.

Scheeren hopes to achieve this transformation through how the building is organised. He pushed for “collaboration and equality”. Imagine the building’s loop as a rope, made from several continuous strands, housing independent worlds, which twist around one another, and sometimes connect – a little like the independent upstairs-downstairs worlds of aristocrats and servants in a stately home. Chief among the loops is the “TV making loop” for the staff, and, wrapped around it, the “public loop”, a continuous promenade open to the public – unprecedented in Chinese architecture – made up of theatrical staircases, processional ways and an unending “museum of media”, with windows one way looking on to the city, and the other revealing the smoke and mirrors of TV, glimpsing into studios and edit suites.

Planning the creation of an unprecedented architectural form on such a vast scale in an extreme earthquake zone was not an easy matter, one finally cracked by Koolhaas’s engineering guru Cecil Balmond, from the London engineers Arup. “Maybe we could best describe it as a tube folded in space,” Scheeren says. “All the outer surfaces are covered in a diagonal steel mesh and this mesh is folded and allows the weight to flow around the building until it finds the ideal path to the ground.” The shape, and the arrangement of the steel cage, was continuously tested and finally chosen by three cross-checking algorhythmic computer programs which simulate nonlinear behaviour in nature, as well as a 64-tonne copper replica in an earthquake simulator. Never before has such a vast building’s form been so dictated by a nonhuman hand.

Alas, its actual construction is left to sheer manpower. CCTV doesn’t fully open until next year – though the façade has been completed for the Olympics, and chunks opened to host its glitzier televised events. You can catch glimpses of the building’s radical internal structure only in the completed, distorted staircases, which look straight out of The Cabinet of Dr Caligari.

You need to visit Portugal’s Casa da Musica to get a hint of what to expect, where a similar “promenade” of Koolhaas’s “intense space”, is wrapped around the central auditorium, offering a succession of jump-cut, cinematic, often uncomfortable architectural experiences. Koolhaas, before turning to architecture, trained as a journalist and screenwriter. It shows. Architecture, to him, is just another form of media.

CCTV isn’t groundbreaking because it’s big, weird-looking, computer-generated or because that look-no-hands cantilevered corner has three 4 metre-wide circular glass floors, so white-knuckled visitors can stand over 162 metres of air – though these would be reasons enough. It’s groundbreaking because it tries to reshape what architecture might be, a space in which the real and the virtual become thrillingly blurred, solid yet ambiguous,– “all qualities that are traditionally Chinese”, Scheeren says. This is not a country of Western rationalism, but of Eastern ambiguity. Of course it might fail. It might end up the ultimate symbol of a tyrannical regime. Then again, it might transform the very landscape of China, and of the West.

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