On July 27, when the Summer Olympics get under way, NBC and television networks across the world will fix London under a spotlight that will barely dim for 17 days. The opening ceremony, overseen by the British film director Danny Boyle, will grab most of the attention on the first night. After that, TV producers, as they churn out more than 5,000 hours of coverage, will search for a building—ideally one of the new venues—to stand, in a kind of architectural shorthand, for the city as a whole.

In Beijing four years ago, the unquestioned architectural star was the main Olympic stadium by Herzog & de Meuron, the so-called Bird’s Nest—a daring, expensive, and preening structure that seemed perfectly to express rising Chinese confidence and ambition. In Athens, it was not an entire building but a bright appendage: the new roof of the main stadium, a bone-white superstructure by the Spanish architect Santiago Calatrava that was added to the existing building as the Greeks rushed to get ready for the 2004 Games.

In London, however, where the main venues are grouped together in a newly built Olympic Park on the eastern edge of the city, in an area known as the Lower Lea Valley, audiences may search in vain for that kind of instant landmark. Thanks to the fragile condition of the global and European economies, the London Olympics have been described as the Neo-Austerity Games, a reference to the last time that the city hosted a summer Olympiad, in 1948. As was the case then, with England emerging still shell-shocked from World War II, the country approached the 2012 Olympics as a chance to prove, or at least test, its pragmatism. Showy extravagance, especially the architectural kind, was out of the question.

The main Olympic stadium, by the American firm Populous (formerly HOK Sport) in collaboration with British architect Sir Peter Cook, was meant from the start to be as self-effacing as the Bird’s Nest is outgoing. Ringed by a simple scaffolding of triangular white-steel supports, it is a lean, impressively utilitarian structure designed to be partially dismantled after the games are over, going from a capacity of 80,000 to 25,000.

Many of the other venues are also temporary in whole or in part. Zaha Hadid Architects’ Aquatics Center is a sleek concrete design weighed down by unfortunate-looking wings for extra seating that will be removed once the games are over, making it a rare example of a building whose second act promises to be more dramatic than its first. If there is a dark-horse contender for TV stardom, it is the Velodrome by London’s Hopkins Architects; the streamlined, cedar-clad building, which will host the indoor cycling events, has already been cheered by several prominent London critics. But it’s also a decidedly minor venue on the periphery of the Olympic park.

Over time, as tends to happen with even the most straitened Olympics, the budget for London’s games has ballooned, growing from a genuinely austere initial figure of $3.8 billion in 2007 to recent estimates of $17 billion or $18 billion. The tab for Olympic security has nearly tripled, to more than $1 billion, as organizers decided they needed not the 10,000 guards originally budgeted for, but 23,000 instead. That is perhaps a sign that extravagance can come in a range of forms, in some cases indistinguishable from nationalism or anxiety in the age of the war on terrorism. The stripped-down main stadium wound up costing $500 million, hardly a bargain.

The British press, of course, has had a field day with those numbers, with the Daily Mail referring to “the ongoing debacle” over increasing costs and the more circumspect Economist condemning the free-spending “Olympic movement” as “a juggernaut controlled by an unaccountable sporting elite.”

Beneath the loud debate over budgets, though, is a more complex, and frankly more interesting, discussion about the master plan for these Olympics and what will happen after the games are over—once the site enters what is known as its “legacy” condition. From the start, London organizers have taken an interest in the long rather than the short view, in using the games as a vehicle for investing in and trying to transform a sizable chunk of East London.