When a pirate named Captain Jack Silver steals the Elements of Harmony and kidnaps the Cutie Mark Crusaders, it's up to Twilight and the rest of the Mane Six who now must take to the high seas in order to get them back. When the Mane Six finally find them, they all soon find themselves joining Jack and his crew on a swashbuckling adventure filled with challenging spirits, terrible storms and demonic pirates, all of which act as obstacles that stand in their way of finding the SEVENTH Element of Harmony.