One day, Applejack happens upon a strange old journal that appears to be written by a master criminal - Black Jack the Outlaw, a mysterious stallion with powers beyond that of any normal earth pony, who terrorized Equestria with his gang of miscreants in days long past. What secrets are hidden in the pages of his old journal?

This, as well as magical mishap at Twilight's place, would trigger a series of events leading to an adventure unlike any the six pony friends have ever encountered before.