Quick recap
Kat and her brother Daniel move into a new house, and their dog Killer sniffs out a moving sponge under the kitchen sink. It's a Grool, a creature that feeds on bad luck. Whoever finds one can't get rid of it, or they die within a day. Trouble comes fast: Kat's dad falls off a ladder after spotting it, and bad luck spreads through the house. Kat tries burying it, smashing it, and feeding it to the garbage disposal, but it always comes back. Her friend Carlo borrows it, and some boys steal it at the playground. Finally Kat finds its weakness: she sings to it sweetly and cuddles it, and it shrinks into a lifeless lump. The celebration is short, because Killer trots in with a Lanx, something even worse.
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