When a deadly virus strikes a loving Fluttershy, and almost destroys her, Twilight Sparkle finds a spell in a forbidden spell book that she found in the library of Trottingham when on vacation to visit her dying grandmother. The spell is dark magic, and it should never be used, but this was Twilight's friend, and she would do anything she could to save her dear, animal-caring, shy, and lovely friend. What's the worst that could happen? Right?