For 500 years, the Cahills have been the most powerful family in the world. For 500 years, they've protected the source of their power - the 39 Clues. And for 500 years, they've kept their secrets silent. Until now. This extraordinary stand-alone novel cracks open the Cahill vault to tell the story of the most coveted piece of artwork in the world, a masterpiece that has been the target of seven separate theft attempts: Jan van Eyck's altarpiece at Ghent.
