Sometime in the early 1950s, weird behavior began to be noticed in some of the nonhuman inhabitants of small fishing towns near the industrial city of Minamata, on the island of Kyushu in southern Japan. Birds tumbled from trees, or flew erratically, occasionally bumping into houses in their flight. Cats walked with a peculiar lopsided gait, or ran in tight circles, eventually becoming totally disoriented and dying. Locals called the condition “dancing cat disease.” Not long after these strange happenings were first observed, abnormalities began to occur in humans as well — abnormalities of increasingly frightening proportions.