Four children are seized by a pair of modern-day Fagins--in a taut, sinister, but nonviolent page-turner. Mr. Smith has found a job in Philadelphia, but just as his wife and five children are about to set off cross-country from L.A. to join him, Mrs. Smith collapses and is hospitalized. Boo, at 12 the eldest, is off on an errand; by the time she returns, a social worker has whisked away the younger four--into the clutches of J.D. and Peachie, bogus foster parents. As Boo searches desperately for them, her brothers and sisters are getting royal treatment in a big, old house with seven other children, while they learn exciting games like ""snatch"" and ""seek."" Soon they're playing these games in other people's houses, in the dead of night. Though the young Smiths' suspicions dawn into certainty, Peachie and J.D. have a tight set-up that seems impossible to escape. While the Smiths aren't take-charge types like the Stanleys in Snyder's The Famous Stanley Kidnapping Case (1985), they're solidly individual, and Curry supplies a rich assortment of background characters. The bad guys' modus operandi is all too plausible. The story does depend on coincidence: J.D. and Peachie's house happens to be near the Smiths' old neighborhood, and their van is distinctive enough to be traceable. In the end, the police descend and the Smiths are reunited; readers will exit with a smile, Fine suspense.