The minions at Castle Hangnail are proud of their place from the minotaur cook to the screwball goldfish. But the castle is in trouble. If the minions don't get a new Master or Mistress it will be sold and demolished to make way for an apartment complex. With the roof over their head and way of life threatened, they are more than anxious to meet the latest Master or Mistress. When Molly shows up, the only thing on her that looks evil are her boots. She's short. She's cute. And she's not properly unpleasant. In fact, she's nice! Eek! The hunchback guardian and talking armor are suspicious but not alarmed. Molly flatters Lord Tinman's fears away by calling him, "stalwart," but the guardian, whom she magnanimously names, "Majordomo," is still worried. If Molly can't complete a series of tasks given by the Board of Magic, they will lose the castle.
As Molly settles in, she makes friends, gardens, learns spells and slowly works through the tasks. She even gets the admiration of the townsfolk when she scares the evil developer out of town after turning a donkey into a dragon. All is well until the real Evil Sorceress shows up exposing Molly's lie and causing hurt with the friends she has made so far, especially Majordomo. The guardian also has to figure out who to be loyal to, a Mistress that is evil or one that is wicked? Molly distinguishes between the two in that wicked is scaring someone by turning them into an earwig, but evil is turning them into an earwig and stomping on them. Even the guardian recognizes that the Evil Sorceress does not love the castle or the minions and has to go.
Molly and the Evil Sorceress are actually friends and Molly explains to Majordomo how "She was mean to me, but then sometimes she'd be sort of nice too." As she thinks about it she realizes that the Evil Sorceress was only nice when she messed up which wasn't really nice at all. Then she thinks about how she'd take her magic and knows that her friend cared more about herself than Molly. Perhaps she wasn't ever a friend.
Molly decides that a witch takes responsibility for what she does and she apologizes to everyone for being an imposter and lying to them. They still accept her as their Mistress and they plan on retaking the castle. Majordomo accepts Molly even though he knows that he might lose the castle anyway. He likes Molly and gets over his fears to help her. Molly, on the other hand, must decide how to proceed with her friendship with the Evil Sorceress whom she now sees as the bully she is. When Molly is faced with getting revenge on the Evil Sorceress, she has to make a choice and between evil and wicked. An exciting climax along with plenty of laughs that is hard to put down.