Nopony is born a megalomaniac driven by an all-consuming desire for power.

When her plan at the Fall Formal is foiled by Twilight Sparkle and her friends, Sunset Shimmer is forced to confront her past. Guided by Harmony, she delves deep into her memories to find the reason for which she had once sought power, before power had become its own reason, and to rediscover the good within herself.

When demons begin to target her friends for their magic, the newly reformed Sunset sees her chance to use the demonic powers remaining in her for good, and decides to become a Devil Hunter.