Slither

From his first terryfying, bloody encounter with them Matt Parker knew they were lethal to the human race. Out of the murky sewers they suddenly attacked - snapping, biting, ripping at his flesh. After the first sensationalism had died down, the media lost interest.....the experts dismissed them as no more dangerous than ferrets or rats.....people started to forget.
But Matt knew different. All the time they were growing in size and numbers - and they preyed on living flesh!