Twelve-year-old Minerva Keene lives in Chicago's luxurious Arcanum building, where she plays tag on the interior balconies and rides up and down the iron-caged elevator. But when someone starts poisoning her neighbors, the smart and spunky girl enlists her daredevil (and accident-prone) brother and the biggest kid at school to help her solve the case! Fortunately, her parents are away, and her babysitter doesn't pay much attention…. Filled with twists and turns, red herrings, and slapstick humor, this fast-paced mystery will captivate readers ages 8 to 12. (AG)