Twelve-year-old twins Nick and Eryn investigate why their mother and new stepfather are keeping secrets, why they are forbidden to meet their stepsiblings, and, most important, why their lives are in danger. Interest Level: 3-6 Reading Level: 5.4 ATOS Book Level: 5.4 AR Interest Level: MG AR Points: 9 AR Quiz: 178928EN Reading Counts Level: 4.6 Reading Counts Points: 15 Lexile Measure: 760.