They have always been among us, being run out, trapped, swept away. Now they want revenge. .. As the city faces the worst heat wave in 150 years, the municipal workers go on strike and the garbage begins to pile up. As it slowly leaks into the street, rats begin to crawl out from under the concrete and the shadows, searching for food. But this is a new, faster breed of rodent, and soon, they are everywhere - creeping out of toilets into beds and over tables. And if the infestation of fat gray masses isn't terrifying enough, it's discovered that the rats are carrying a horrible virusà deadly to humans.