Quick recap
A week before Halloween, the goddess of magic Hecate asks Percy to house-sit and watch her pets: the hellhound Hecuba and the polecat Gale. In return he gets his second letter of recommendation. Percy calls in Annabeth and Grover and plans a Halloween party for camp. But Grover drinks a strawberry potion, the house is wrecked and the pets escape. The hunt takes Percy to Troy and to perfume shops run by grudge-holding naiads. On party night, an army of ghosts gets out of control. When Hecate comes back, Percy has to tell her what happened.
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