In this third book in the Charlie Thorne series from bestselling author Stuart Gibbs, Charlie tracks down Cleopatra’s greatest treasure in Egypt. Charlie Thorne is a genius. Charlie Thorne is a renegade. Charlie Thorne isn’t going down without a fight. After tracking down incredible discoveries by Einstein and Darwin, Charlie is back. This time, the great ruler Cleopatra has left behind an extremely valuable and powerful treasure, its location encoded on an ancient stone tablet.