Big Bad Read

This is really hard: choose who you think is the most evil character in a children's book in Bloomsbury's Big Bad Read competition.
I can't decide between Bill Sikes from Oliver Twist (I'll never forgive him for beating up Nancy), Voldemort, The Child Catcher from Chitty Chitty Bang Bang, or Narnia's White Witch. I would have chosen the Dark Riders from Lord of the Rings, but they aren't on the list.
Eoin Colfer's favourite all time baddie is Captain Hook.
Michael Morpurgo chose Long John Silver from Robert Louis Stevenson’s Treasure Island.
You can place your vote online here.