100 years ago, in a small kingdom situated far east of Equestria called Withersham, a group of stallions were given the task to save their home from an evil sorcerer named Black Mist, a former wizard that once served Withersham's loyal ruler King Icarus. Consisting of two unicorns named Ares Maverick and Silver Iron; an earth pony named Colt Daring, and a fire pegasus named Piston Ace, the group of stallions call themselves the Four Horsemen. The stallions battle their nemesis with the use of the king's newest creations, the Gems of Peace, and thought they'd won...until the tables were turned on them as Black Mist turned them into stone with the use of his dark magic. However, Ares Maverick was able to give Black Mist the same fate as he and his group had suffered and all were turned into stone.

Now years later, in present day Equestria, Twilight Sparkle has known about the legend of the Four Horsemen through books and is determined to find out about the Four Horsemen's whereabouts...and she must do so quickly before some force of evil finds Black Mist.