What if the most terrifying person you know is your ten-year-old sister? Seventeen-year-old Aussie Che Taylor loves his younger sister Rosa. But hes also certain that shes a diagnosable psychopathclinically, threateningly, dangerously. Recently Rosa has been making trouble, hurting things. Che is the only one who knows; hes the only one his sister trusts. Rosa is smart, talented, pretty, and very good at hiding what she is and the violence shes capable of. Their parents, whose business takes the family from place to place, brush off the warning signs as Rosas acting out. Now that they have moved againfrom Bangkok to New York Citytheir new hometown provides far too many opportunities for Rosa to play her increasingly complex and disturbing games. Alone, Che must balance his desire to protect Rosa from the world with the desperate need to protect the world from her.