After being assigned to test the capabilities of her brother's security measures herself, Twilight was happy that her friends were willing to join. However, Rainbow Dash makes the mistake of questioning the skills (or lack thereof) of Shining Armor.
After chasing a thief from Canterlot to the desert, Twilight and friends are beset by misfortune. Now, Twilight must delve Equestria's greatest secrets, and discover a truth that even she will wish she hadn't.