Earwig was left at St Morwald's as a baby. Unlike the other children, she loves it there, mostly because she has the run of the place and seems to be able to persuade people to do as she wants. Then one day Earwig is chosen to live with a very strange couple: Bella Yaga, her new 'mother', is actually a horrible witch. Earwig will need all her ingenuity (and some help from a talking cat) to survive...