NEW YORK—Perplexed executives at NBC announced Monday that the network has canceled the new series City Buds, after the half-hour sitcom garnered abysmal ratings despite a flawlessly executed $250 million marketing strategy.

Even with smart, nuanced, consistently high-quality billboards, the sitcom only lasted four episodes.

According to NBC's marketing department, the series premier of City Buds, a show about two male friends who reside in Chicago, performed exceptionally well during the eight minutes preceding its first commercial break. But then, for some unknown reason, the ratings plummeted. The incomparably hyped show never recovered in the following weeks, and the decision was made to scrap City Buds after just four episodes.

"We can't for the life of us figure out what went wrong," NBC Universal vice president of marketing Maureen Murphy said. "We had the leading creatives in the business working on City Buds. The best copywriters, top-notch PR guys, not to mention a world-class graphic design team. From the moment we started branding the show, we did everything perfectly."

"Maybe we didn't make it clear enough to viewers that this was a new comedy from the producers of How I Met Your Mother," Murphy added. "But we ran that over and over in all of our TV spots. I just don't know."

Members of NBC's marketing department struggle to figure out where they could have possibly gone wrong.

City Buds, which, in addition to the two incompatible roommates, featured a comical dog and a grumpy Latino landlord, was the subject of the most intensive advertising campaign in NBC's history. Beyond the typical Internet, billboard, magazine, newspaper, television, and radio ads, the network also employed cutting-edge guerrilla marketing techniques, including a sticker campaign, personal canvassing, and 14,000 urinal communicators installed in public restrooms across the U.S. that, when activated by a stream of urine, informed patrons of the date and time City Buds was scheduled to air in their market.

"There was something for every demographic in this campaign," senior brand manager Earl Kinney said. "I don't understand why, at the very least, Caucasian males in the 12 to 24 set didn't tune in. How could they not identify with these kinds of promotional devices?"

Kinney added that it was "inconceivable" that a television program supported by 1.25 million promotional coffee-cup sleeves could perform so poorly.

Most disappointing to NBC executives was a weeklong interactive "roadblock" the network purchased on the home page of the popular social-networking website MySpace. The full-screen pop-up ad described the series as "Just Shoot Me on a half-caff cappuccino—to go!"

Experts say that, while there have been  several documented cases in the past of television programs underperforming in the face of brilliant marketing campaigns, a direct cause for the bizarre phenomenon has not yet been determined.

"We may never know what the 'X-factor' is that can turn an expertly marketed show into a complete failure," said Richard Bertrand, an analyst at the ACNielsen market research firm. "Who can say why the masterfully promoted Studio 60 on the Sunset Strip, for example, was canceled after just six episodes, while a show such as The Office, which quietly debuted in an undesirable time  slot, is now one of the most successful shows on network television?"

Due to the failure of City Buds, NBC said it will redouble its marketing efforts for the show's midseason replacement, Nerds!, a sitcom from the creators of City Buds starring David Hyde Pierce.