It was the most expensive residential listing in New York City.

Remember when Penthouse 40B at Fifteen Central Park West was such a gloriously shiny token of our breathtaking real estate bubble? A certain foreigner--maybe a London-based investor--signed a contract in 2005 for the 5,276-square-foot, 14-foot-tall, 9.5-room, four-bedroom penthouse, and closed at the end of this April for $21.5 million. He took out a $14.5 million mortgage with JPMorgan Chase that same day, records show, which means it only cost $7 million cash. And within a few weeks the sprawl was on the market with Brown Harris Stevens for $80 million, just about four times the price of the condo.

It was the most expensive residential listing in New York City. And now it's gone.

"Coming off the market as of today," one of the listing brokers, Richard Wallgren, just told The Observer. "The owner is deciding what to do with the apartment, whether to move in, whether to sell it later. It's off the market."

"I showed it a good deal--to very qualified people," the broker said. "And they loved it, but it just didn't click with the people that saw it." Were there offers for an $80 million penthouse that cost $21.5 million a few months ago? He wouldn't comment, except to say, "I think there is an element of some paralysis, but I think the bubble surrounding this building is very much intact."

High-end brokers like Mr. Wallgren have been passionately declaring that super-luxury Manhattan real estate is still immune to the city's woes--even when there's mounting evidence to the contrary.

Apartment resales at Fifteen Central Park West, just a few months ago, were supposed to be smashing the $100 million mark. Now the building is left with only venture capitalist Lindsay Rosenwald's very unofficial $90 million listing (he paid $30 million). As far as the official listings go, Streeteasy puts the four next-highest listings at $30,000,000, $21,250,000, $18,495,000, and $9,995,000. All four have recent been price-cut.