Summerfield's debut owes much of its charm to its saucy, wise- child narrator, 11-year-old Cassie Wade, whose school chum Margie Thoroughgood, ``the girl who had everything''--blond hair, big blue eyes, a developing bust, and a splendid, shiny silver bike--stepped into a green car and was never seen again, imparting terror to all the parents and a certain notoriety to the village of Upper Grisham. Mrs. Thoroughgood befriends Cassie--begins, in fact, to obsess about her--and when Cassie's dad is abroad and her remarried mum is not eager to deal with her, Mrs. T. invites her to move into Margie's old room--and dress in her dresses and ride her bike. Mr. Thoroughgood is away for a spell, perhaps permanently. Time passes: the police make little progress in the case; Mrs. Thoroughgood becomes more and more Margie/Cassie obsessed; and the villagers feud among themselves--first assigning Margie's abduction to Cassie's dad, then to his artistic Welsh boyfriend, then to the hapless village idiot--before Margie's body is found past the dell, and an old alibi breaks down. Splendid evocation of country schools, English landscape, tinkers, and village mores: Anglophiles will queue up for this one.