“I’m a tremendous fan of your work,” he told the Hawaiian-shirted auteur, and he repeated his name. A companion of Mr. O’Horgan’s reminded him that Mr. Braff is the young man who’s buying his Greenwich Village loft.

“Z-A-C-H,” the actor said. “B-R-A-F-F.”

According to city records, Mr. O’Horgan’s 2,500-square-foot apartment is on a top floor of 840 Broadway. Maybe Mr. Braff knows that actress Heather Graham, who has guest-starred on his show Scrubs as Dr. Molly Clock, happens to be in the building’s penthouse.

Mr. O’Horgan and three other long-term building owners have been there since the 1970’s: “Eighth Street was happening, Saint Mark’s Place was happening, it was kind of a hippie thing,” one of those owners told The Observer. “But everyone that came down sort of took a chance.

“We all bought a floor for like 20,000 bucks, but mine was still being occupied by a guy making stuffed animals.”

The longtime owner, who bought in 1971 and who is also a co-op board member, said the Braff deal isn’t official yet. “We haven’t seen his financials, we haven’t seen anything. In the old days, it would probably be no question; now people do look at references and financials and things like that.”

Mr. O’Horgan, whom Newsweek once called “the Petronius of our theatrical decadence, the drag-haberdasher of the lumpen-avant-garde,” fills his loft with a collection of global musical instruments, the board member said. “He’s a true saint—he’s a great guy, just an incredible human being.”

It’s hard to tell how much old Petronius’ apartment would cost Mr. Braff if he can close the deal, especially because it isn’t officially on the market. The resident says he thinks “it would go for a little over $3 million.”