"Twelve-year-old Minerva Keen forms a detective club to uncover who is poisoning residents of her storied Chicago apartment building, knowing that any one of her neighbors could be the poisoner--or the next victim"--

Tandy Angel is, along with her brothers, a suspect in their parents' murder but having grown up under Malcolm and Maud Angel's perfectionist demands, Tandy decides she must clear the family name no matter what.

As she fights for the family company, Tandy Angel's detective prowess is called into question and her paranoia builds, forcing her to face the possibility that her stalker could be all in her head--or the very real danger that will finally bring her down.