It was just another hot summer afternoon for 12-year-old Nathan Cole. Until the unthinkable happens. A daring attempt to abduct him, orchestrated by his newfound enemy, Dan Perry, thrusts Nathan into a deadly game of cat and mouse. At stake is the mysterious bookcase in Nathan's attic, rumored to contain a monumental and potentially lethal secret put there by his ancestor Thomas Hammond in 1850. Fully aware of the danger, and refusing to sit idly by, Nathan takes matters into his own hands with the help of his best friend, Gina McDermott. What follows is a high-stakes series of twists and turns, including the discovery of a piece of sheet music from the 1700s, and a cryptic message left behind by 19th century apothecary Nicholas Graf. As the tension mounts, Nathan's family is forced to take drastic measures to ensure his safety. But will it be enough to save him from a powerful adversary, one with unlimited resources, who will stop at nothing to get what he wants? Is this the end of Nathan Cole and the mysterious case of secrets in his attic? Will Gina get caught in the crossfire? See what becomes of the boy whom the media has dubbed "the most famous 12-year-old detective in the world," as he tries to survive the riddle of The Grim Fugue.