内容简介：Hold your horses! Jack and Annie must find four secrets of greatness for Merlin the magician. To start, they travel back in time to meet Alexander the Great. He should know all about greatness, right? But young Alexander is bossy, vain, and not great at all! How can they learn from him? It’s going to take a wild black stallion, magic from Merlin, and a lot of bravery to succeed. Are Jack and Annie clever and bold enough to complete their mission?