By BILL CARTER

On "The Runner," a reality-television show that ABC will introduce in September, the central figure will try to cross the country undetected, completing a series of tasks in pursuit of a $1 million prize.

During the journey, the runner just might be instructed to buy a Big Mac and fries at, say, a McDonald's in Ohio. For McDonald's, this might mean a healthy dose of TV time as the contestant races to complete the task. And with people across the nation trying to find the runner to take the prize, business might pick up at McDonald's throughout Ohio.

Or the runner might be told to step inside a Starbucks for a decaf latte or dial a number on a Nokia cell phone or pull out a Citibank ATM card for a cash withdrawal.

Such moments will not be commercials strictly speaking, but they will be enormous opportunities for revenue, above and beyond whatever ABC takes in on the standard 30- second commercials that appear during breaks in the show.

In its extensive use of paid plugs that are completely integral to the show's story line, "The Runner" is the most ambitious use yet of advertising within the content of entertainment programming. The network invited more than 120 advertising executives to a special presentation of possible sales opportunities last week on the set of "Good Morning America."

The program comes amid intensifying concerns in the broadcast industry about how networks can retain the bulk of the corporate advertising budgets despite their ever-diminishing share of audience. Advertisers are eager to find ways to present their products to the most possible viewers as hundreds of channels, available at the flick of a remote control, make traditional commercials increasingly easy to avoid.

"Advertisers are clamoring for creative and innovative ways to reach consumers," said Bob Flood, senior vice president of Optimedia, a buying service for advertisers. "Product placement is a way of enhancing an advertiser's message."

"The Runner" is likely to inflame critics who have excoriated networks for squeezing commercial messages into every corner of a consumer's consciousness. Michael Jacobson, the executive director of the Center for Science in the Public Interest in Washington, a public advocacy group that deals with a range of issues from nutrition to commercialization, called ABC's plan to embed commercials in "The Runner" a "new level of prostitution for broadcasters."

"Should advertising be directed at us all the time?" Mr. Jacobson asked. "And if it is, should it pretend to be entertainment?"

ABC executives have no hesitation about their plans. Indeed, they are showing unusual confidence in "The Runner," a concept more than a year in refinement that was brought to the network by the acting-writing team of Matt Damon and Ben Affleck. Under the rules, any viewer who "captures" the runner by spotting him
or her and calling a network hot line can claim whatever money the runner has made to that point. It is ideally constructed to mesh with the Internet because clues and information can be exchanged on the Web.

At the presentation, ABC had a direct message for the advertisers: "The Runner" is going to be a giant hit with millions of viewers, and the smart advertiser will sign up quickly to be everything from the official car the runner drives in making his escapes to the official pants he wears.

Product placement has been increasing on television, fueled particularly by the surge in reality shows. The concept itself reaches back to the early days of television when most shows were fully sponsored and the advertiser's products from Camels to Chevrolets ? were often prominent on camera. Companies have been paying for years to have their products prominently used by stars in movies.

But the practice has gained new life as advertisers have grown more concerned about the zapping of commercials. A show on the UPN network in 1999 inserted computer-generated images of Coca-Cola and other products into the content of a show called "Seven Days."

The NBC soap opera "Passions" built a plot line around a book that was supposedly the diary of one of the characters. The book, "Hidden Passions," published by HarperCollins, became a best seller in real life. ABC's own "Who Wants to Be a Millionaire" has included what Mr. Davies called "the perfect seamless product placement," when the host, Regis Philbin, invokes the name of AT&T to make the calls for contestants seeking help from a friend.

But the apotheosis of recent product placement has surely been achieved by the CBS show "Survivor." Contestants have worn Reebok shoes, used towels from Target stores and sated four days of hunger with generous helpings of Doritos. Last week's episode of the series contained perhaps the longest in-program commercial in television history. A contestant, Colby Donaldson, won a Pontiac Aztek automobile in a competition in the Australian Outback, where the show takes place. Overjoyed, Mr. Donaldson gushed for several minutes over what he described as the car's elegant interior and roomy cargo hold. Pontiac Aztek is a sponsor of the show.

Mr. Shaw said, "Placement has been used effectively on `Survivor,' though I think bringing out those bags of Doritos when they were starving seemed a bit awkward." Advertisers paid roughly $12 million each to sponsor "Survivor."

The roster of potential sponsors for "The Runner," Mr. Shaw said, could easily include everyone from McDonald's to Home Depot to The Gap. "We've already had a number of people approach us," Mr. Shaw said. Pepsi was on board early, grabbing an exclusive on the soft-drink sponsorship.

The best opportunities for placement, Mr. Shaw said, are likely to come during the tasks the runner must accomplish to add to his money total. He or she may get as many as 20 assignments over 13 weeks, and several of those would be related to sponsors. McDonald's, for instance, might sign up in hopes of receiving valuable screen time, increased traffic at some locations, positions on the show's accompanying Web site, and mentions in the clues that will be posted both on the Web site and on other ABC shows like "Good Morning America."

The potential benefit to such advertisers is unpredictable, and, at the moment, incalculable, Mr. Shaw said. "I don't know how to monetize this or find the formula for what to charge," he said. "McDonald's could get three minutes and 11 seconds of screen time. You can't do something formulaic like charge a price for each second of screen time."

Instead, he said, ABC is likely to structure deals so that sponsors of "The Runner" increase their entire spending budget with the network.

But he emphasized that he would plan to sell only six or eight of the tasks, saving the others for noncommercial locations like the Bronx Zoo.

He also said clues would not be too specific about where the runner might be on a given day, to avoid the prospect of "100,000 people turning up at a McDonald's in Cleveland."

Beyond the sponsored tasks, ABC will be looking to sell other aspects of the runner's on-camera life.

"If he needs a car we could see the front of a Chevy Monte Carlo, and then the back," Mr. Shaw said. "We could be inside the car for some time."