Princess Celestia feels that Ponyville is over populated with ponies and she has not been a good leader like she once was. She fears rebellion and being overthrown, so she seeks Princess Twilight Sparkle's help and together, they come up with the most evil and horrific plan. After they follow through with their plan, Twilight Sparkle needs to cover up the facts about what just happened and pretends to give help and aid to those who are suffering and dying, by presenting new medical practices that nopony had ever heard of before. It's up to Twilight Sparkle's friends to uncover the truth about what happened to Ponyville and to discover the horrors that lie behind these new medical treatments.