Eleven-year-old Madlyn and her younger brother, Rollo, are sent to stay with their great-aunt and -uncle Clawstone at crumbling Clawstone Castle, only to be embroiled in the castle's financial troubles; the castle must attract more paying visitors to maintain its legendary herd of Wild White cattle. To compete with a nearby attraction, the castle needs some chills and thrills, so the Clawstones select some vulgar, terrifying ghosts and set up such a frightening show that tourists scream, faint, and retch--only to return with their friends. Through the machinations of some unknown persons, however, the Clawstones lose the cattle, leaving the children (and the ghosts) with a mystery to solve. Plot embellishments are sometimes distracting, and the convoluted story comes together in a series of coincidences. Ibbotson's charismatic ghosts are great, however------as human as they are horrific--and there's plenty of quirky humor in this energetic, diverting read, loaded with charm.