Chaos isn't just a theory in the Passamaquoddy Bay.

Here in the waters off of Eastport, Maine, lurks the Old Sow, the western hemisphere's biggest whirlpool.

She shows up wherever and whenever the spirit and tides move her, occasionally opening her maw suddenly in the form of a madly spinning, 40-foot-deep hole in the ocean, several hundred feet wide.

Sometimes she's more subdued, creating a funnel-shaped hole roughly 12 feet wide and 12 feet deep.