As any child knows, the steam breaking through the manhole covers in Manhattan in winter (and sometimes in summer too) comes from alligators in the sewers making cups of tea. Likewise, if an unidentifiable carcass washes up on the beach of the East River it must be a creature from space.
Oddly, while the children figure out quite quickly that alligators in the subway system is nothing but silliness, the adults fall for the Martian Invasion Myth with remarkable frequency. In 2008, we got our knickers in a knot about the Montauk Monster, a bloated carcass that rolled ashore on Long Island. But that was four years ago.
Thank goodness then for Denise Ginley, a freelance photographer who, on a stroll last Sunday on the eastern bank of Manhattan Isle, spotted something weird on the sand under the Brooklyn Bridge, took a few snaps and zipped the images to the city's social blogs.
"We took some camera phone pictures and then finally decided to come back with my camera and I got up the courage to climb over the fence and get closer to it," Ms Ginley told the site, ANIMAL. The headline writers called it the "East River Monster", while some speculated it was the biggest rat the world has ever seen.
The Parks Department spoiled everything by saying in was nothing more than a pig, presumably discarded after a July cook-out. Yet something doesn't quite convince. The pictures taken by Ms Ginley clearly show toes ... not trotters. So the mystery endures.
All of the city is on edge and even the alligators have stopped making tea. What it definitely is not is a cousin of the Montauk Monster of 2008. That, rather boringly, turned out to be a semi-decomposed raccoon.