(FORTUNE Magazine) – It is one of the eeriest Manhattan landmarks: In glowing red neon atop Midtown's Tishman Building is 666--better known as THE MARK OF THE BEAST. A beacon to Satanists? Well, no, says Arthur Bocchi, a senior managing director with Sumitomo Realty & Development, which owns the building. The numbers, he says, simply denote the building's address, 666 5th Ave., and have been there since it was constructed in 1957.

A likely story.

FORTUNE took a field trip to investigate, keeping an eye out for any devilish goings-on. We visited the building's 13th floor (yes, it actually has one) and found...a Smith Barney office. Undaunted, we quizzed a lobby security guard, Andy Hernandez. Anyone ever come in and bite the head off a chicken? "No." Any pentagrams drawn on the floor? "No." Ritual sacrifices? "No." Hm. Pretty much the only debauched rituals in the building's past, it seems, were the high school proms that took place at Top of the Sixes, a restaurant that used to occupy the building's top floor. That space is now occupied by an exclusive cigar club--which may be annoying, but not, strictly speaking, satanic.

Disappointed, FORTUNE was about to leave when a knowledgeable source imparted that a couple had once been caught copulating in one of 666's elevators. Aha! The devil, no doubt, made them do it.

--Jeremy Kahn

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