Which Witch?

"Which Witch?" is a children's novel written in 1979 by Eva Ibbotson.

Plot

The main character, a wizard named Arriman the Awful, finds himself bored one day with his dastardly doings. When it is prophesized that one day a wizard whose power is darker than Arriman's will take over the burden of smighting and blighting, Arriman is overjoyed. Nine hundred and ninety days, later, however, the wizard hasn't shown up. Arriman's secretary, Mr. Leadbetter, and his butler, a one-eyed, sword-swallowing ogre named Lester, suggest that he marries so he could have a son, Arriman is not pleased. ("A great black crone with warts and blisters in unmentionable places from crashing about on her broom! You want me to sit opposite one of those every morning eating my cornflakes?") In the end, however, he consents.

He decides to invite witches from his hometown of Todcaster to take part in a contest that will decide whom he will marry. Whichever witch performs the blackest act of magic will be his bride. However, most of the witches of Todcaster are downright revolting and nasty. The exception to this is Belladonna, who, even though she is beautiful and secretly loves Arriman, is a white witch.

While walking about town by herself one afternoon, she passes by an orphanage and sees a small boy crying. His name is Terrence Mugg and his only friend, an earthworm he calls Rover, was hurt by the orphanage's wicked Matron. Belladonna heals Rover, and when Matron confronts Terrence, Belladonna suddenly roots Matron to the ground. Belladonna realizes that Rover may be her familiar, an animal that accompanies witches everywhere and helps them perform their magic. She takes Rover and Terrence home with her and together with Mr. Leadbetter and Lester they plan to win the contest.

While the other witches' magic goes hilariously or horribly wrong when it is their turn in the competition, there is one problem Belladonna didn't count on. Madame Olympia, an truly evil enchantress from London joins the contest and is willing to do anything to make sure she will win the hand of Arriman. Olympia wears a necklace of teeth, all of them from her former husbands, who "mysteriously disappeared after they wrote their wills leaving all their money to her".

After spending time with Arriman, Terrence discovers the perfect piece of magic for Belladonna to do: raise the ghost of Sir Simon, Arriman's friend. Will the whitest witch be able to pull off the blackest magic?