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Two ten-year-old girls, Ari and Mandy, vanish from the grounds of Null House one evening. One is found the next morning, so traumatized she can't remember what happened or even who she is--the first ten years of her life erased. A barrette in her hair identifies her as Ari. Since her mother is dead, an uncle and aunt arrive and take her to live in another state. Her memory of the lost years never returns.