'Thick brown bodies, some as large as a foot, slithered like fish beneath the surface of a muddy pond...'

Sarah McGraw lives with her father and younger brother on the edge of town, beside a huge garbage dump that her father helps manage. But it's growing out of control. As the piles of refuse grow, so do the rats that frequent the dump. But not only are they growing - they're mutating ...

Turning against humans, they begin to venture outside of the dump, invading the neighbouring houses through the drains, up into toilets and jacuzzis, harassing the neighbourhood and massing for violent and often fatal attacks on the inhabitants. When one of the dump workers is eaten alive by rats, Sarah's dad is called in to work urgently to try and control the crisis - leaving Sarah and her little brother alone - and at the mercy of the rats ...