Tom Edison and his friends become embroiled in a mystery involving his "double-great" grandfather's inventions, a secret society, and a vendetta being carried out by a descendant of inventor Nikola Tesla. Interest Level: 3-6 Reading Level: 6.3 ATOS Book Level: 5.7 AR Interest Level: MG AR Points: 8 AR Quiz: 140563EN Reading Counts Level: 5.7 Reading Counts Points: 12 Lexile Measure: 880 Fountas & Pinnell: T.