The multipronged attack (books, playing cards, online games, prize sweepstakes) of the 39 Clues extravaganza dashes onward in this second book. Korman takes the reins from Rick Riordan, responsible for series opener The Maze of Bones with barely a hitch as Amy and Dan Cahill continue their quest to solve the mystery of their wide-ranging and powerful extended family (a tree that branches from Mozart to Picasso to Snoop Dogg). The siblings’ bickering increases as they hunt down the next clue, but so do their successes as they manage to be always one step ahead of their various cutthroat cousins.