Pipe down, Faith Popcorn! Richard Welch is the lanky 30-year-old Brit ad genius of the moment, recently hired by the advertising mega-firm Ogilvy and Mather to head the New York office of Crystal, a new division that tracks and analyzes "leading-edge" trends. Mr. Welch's quarry: those voguish developments in society's underground that could help mainstream companies better market their own brands.

Just don't call him a "cool-hunter." He hates that.

He's a cool-hunter.

While a student at the University of Liverpool, Mr. Welch had his own radio show and threw acid-house parties in the back of pubs. After graduation, he worked at a small music-marketing company, helping foist French electronica (then the "least hip," he said) on the U.K. At 23, he formed his own event-marketing company, Reverb, building a monthly dance party around the electronic act Basement Jaxx. Time Out ranked it the best bash in London. He also had a hit in Fabric, a nightclub in the Smithfield section of the city, which he successfully positioned as an anti-glam alternative to the V.I.P. superclubs popular at the time.

All that nightlife was fun, but eventually "the Man" beckoned. Mr. Welch got a position at Headlight Vision, a traditional branding consultancy, where he began to interpret leading-edge trends to help large, established companies like Motorola, Nokia and Guinness. A contact from that job led him to Ogilvy and this tale, bringing ever-slicker accounts: I.B.M., American Express, Kodak.

"Big companies can get it wrong quite easily," Mr. Welch said the other day in his tchotchke-filled office, wearing this generation's answer to the gray flannel suit: white Converse All-Stars, designer jeans and a collarless black-and-white-striped shirt with striking lime-colored cuffs. "They think they know what's going on because they read about it in The New York Times , and often it's not the case."

Mr. Welch and a colleague in London, Zoe Lazarus, enlist a global network of 140 "cultural correspondents" from over 35 countries to file periodic reports about emerging trends in their locales. Now that's reporting! These handsomely compensated freelance trend-watchers include journalists, fashion designers, extreme athletes and D.J.'s. The postcards from the edge come in the form of written reports, magazine features, video footage, musical recordings and T-shirts-like a Wesleyan college application run amok.

Mr. Welch is responsible for sifting through the dispatches and intuiting the larger cultural meaning therein. Recently, for example, he declared the tremendous rise in popularity of VonDutch trucker hats the manifestation of something called "the rise of anti-cool." If it were one year ago, Mr. Welch said, he would have advised companies to go through their back catalogs for products that are traditionally deemed "uncool," then push those products with a knowingly ironic slant.

He has zero regrets about leaving his indie roots to work for a behemoth like Ogilvy and Mather. "I'd rather work with big businesses to help them to do it right, so they're understanding these trends and not just bandwagon-jumping," he said. "This whole concept of 'selling out' is ludicrous."

-Blair Golson

According to William Lever, an account manager with Ogilvy & Mather's London office, and one of several on the scene, the product to which the costume-jewelry queen had lent her gold-plated name was the Fillet Tower Burger, a hefty treat that, alas, will be available only in Britain.

"It's chicken fillet, hash brown, cheese, mayo with ketchup at the bottom and a bit of everything," Mr. Lever explained with relish. "That's why it's called a Tower."

The commercial, as saturated with double-entendre as the Fillet Tower Burger undoubtedly is with calories, opens on Mrs. Trump, resplendent in a royal blue dress and lots of jewelry, as she emerges from her limousine and overhears some sad sack, played by comic Ryan Stiles, telling another man, "I've got this mad urge to buy a Tower." Mrs. Trump naturally assumes he means the kind with arresting views of Central Park and a 24-hour concierge service.

"Ooh! I love a man with a tower," she coos.

"The other version of the burger, please," barked Tim Pope, the commercial's director. The crew had been shooting since 7 A.M. and it was now nightfall. I asked Mr. Lever what the other version included, guessing bacon. But he said it was the same burger, just a different box.

At that moment, a horrible clatter arose down the block. It was Margaret, the nag who normally pulls the carriage in which Mrs. Trump and Mr. Stiles were now filming. Margaret was expressing her dissatisfaction at being momentarily hitched to a lamppost by putting a serious hurt on a newspaper box with several solid kicks. Then some street musician started playing the bagpipes on the other side of Park Avenue. That's not the sort of thing that conjures up Big Apple chic to the average Brit, or for that matter enhances Mrs. Trump's "Diamonds Are a Girl's Best Friend" allure. Speaking of which, I feel compelled to report that she looked absolutely fabulous. For all the horror stories one hears about cosmetic surgery, Ivana Trump is living proof that with enough money and the right doctor any woman can look like a chick in an Archie comic.

To my disappointment, Mr. Lever informed me that the tower-loving line had been cut, though he denied that its Freudian overtones caused Mrs. Trump to exercise script approval.

"She's really good fun, absolutely into the concept," insisted Marcus Vinton, another member of the Ogilvy & Mather team that had flown in for the shoot.

A break was called and Mrs. Trump stepped off the carriage like Cinderella as a crowd of cops, tourists, homebound commuters and paparazzi (most of whom seemed to be in the employ of Kentucky Fried Chicken) formed a respectful semicircle around her. However, nobody was permitted an audience except for a handsome young man in a velvet sports coat who chatted with Mrs. Trump as an equal while she held up one side of a copy of the British tabloid The Sun as he held up the other and the cameras flashed away.

"That's Bill Coles," whispered a publicist. "He covered Louise Woodward for The Sun."

Britain may be the only nation on earth whose journalistic standards are more shameless than our own. To wit: The publicist explained that The Sun was the Fillet Tower Burger's "media partner," which apparently gave Mr. Coles exclusive access to Mrs. Trump.

"He would say, 'You'll never guess what happened to me,'" explained the publicist, predicting the sort of caption that might run under the picture. "'I met Ivana.'"

Unfortunately, I didn't. After the photo op, Mrs. Trump was ushered into her blocklong black limousine for the ride to her Winnebago, which was parked on the corner. Luckily, Mr. Stiles, after shooting an "E.P.K.," an electronic press kit on the making of the commercial, made himself available for a brief interview.

Working with Mrs. Trump was a pleasure. "She has a better sense of humor than I thought," he said, "and she loves her chicken." He added that the unalloyed affection New Yorkers displayed for their queen-now that Leona Helmsley has come into her inheritance and no longer has to work for a living-had taken him somewhat by surprise. "Now I know what it feels like to be in a parade," he said. "She's constantly waving to people."

Mr. Stiles, who enjoys a cult following in England as a member of the cast of the improv program Whose Line Is It Anyway? and appears in the United States on The Drew Carey Show , confessed that Mrs. Trump's former husband came up in conversation, though only briefly. "I told her I worked with Donald," he confided. "She said, 'Oh.'"

Suddenly, the limo returned-in reverse. Apparently, it hadn't deposited the hard-working Slav at her Winnebago or taken her ahead to the Plaza, the shoot's final location, where her word was once law and where the rain that was now falling would undoubtedly mingle with bittersweet memories. For the next half-hour, the car didn't move at all as the crew shot its door opening and closing while Mrs. Trump sat inside not doing much of anything except being a good sport.

The ad's climax comes after Mrs. Trump goes off with Mr. Stiles in the hopes that he's going to buy her a skyscraper. Of course he purchases a Tower burger instead. "So, Ivana. Have you had a Tower before?" he asks guilelessly. Swallowing her disappointment that he isn't a billionaire and possible boyfriend material, "She bites into the mighty burger," according to the script, and then vanishes into the Manhattan mist with Mr. Stiles as the words "Finger Lickin' Good" run across the screen.

However, the Ogilvy & Mather people warned me the finished commercial may depart from the script thanks to Mrs. Trump's creative input.

"She's been brilliant at improving the end line of the commercial," said Mr. Pope, who unfortunately couldn't recall the precise nature of Mrs. Trump's contribution since he couldn't hear it. "We were in the middle of a bloody traffic jam and then somebody started to play the bagpipes," he complained as the rain ran down his eyeglasses in rivulets.

The church ladies who run the bookstore at St. Bart's were also a little peeved, reporting that business in religious books and trinkets had come to a standstill because of the commercial shoot. "They blocked our store and nobody came in," one of them groused.

It also looked as if the 5:30 service was going to be a bust. Still, that didn't seem to dampen the enthusiasm of several male choir members who stood at the top of the church's stairs in flowing white and blue robes and watched the crew strike the set. Not only had Ivana Trump graced their presence, one of them noted, but it was also Epiphany.

"Our cup runneth over," he said, his eyes rolling heavenward.