Twilight discovers a book on her doorstep titled 'The Legacy of Grimoire Fantasia'. All her friends fear the name, but she doesn't know why. A reluctant ally in the form of a familiar showoff illusionist unicorn presents itself and the two set off on an adventure to seek out the truth of Grimoire Fantasia's legend.

However, with the story itself being as dangerous as it is, the two mares may be in for more trouble than the trip is worth. With three entirely different groups on their tails for the powers hidden within Grimoire's tome, will they be able to learn his secrets before the very secrets become their downfall?