Thirteen-year-old Dan Cahill and his older sister, Amy, thought the search for the thirty-nine clues leading to the source of their family's power was over, but when Cahills are kidnapped by the Vespers, Amy and Dan find themselves with only a few day to fulfill a bizarre ransom request before their friends start dying. Part of the "39 Part 2 Cahills vs Vespers" series. Interest Level: 3-6 Reading Level: 4.9 ATOS Book Level: 5.3 AR Interest Level: MG AR Points: 7 AR Quiz: 145649EN Reading Counts Level: 4.5 Reading Counts Points: 12 Lexile Measure: 730 Guided Reading Level: T.