Everyone who came across the strange gym class was looking for something else. What they found was mysterious Mrs Powell with her silent feet and unnerving stare and pashki, a lost art from an age when cats were worshipped as gods. But Ben and Tiffany wonder: who is their eccentric old teacher? What does she really want? And why are they suddenly able to see in the dark? Meanwhile, in London's gloomy streets, human vermin are stirring. Ben and Tiffany may soon be glad of their new gifts. But against men whose cunning is matched only by their unspeakable cruelty, would even nine lives be enough?