After going for a snack in the kitchen, Spike finds a can of green glowing powder. He tastes it, and finds that it would be a good addition for the cupcakes in Pinkie Pie's party at the following day, and so suggests Pinkie to bake them for the following party. She happily agrees, and bakes the cupcakes and serves them the following day.

However, strange things start to happen. It would appear, that anypony who ingests the powder and another pony would tell them something, they would physically take the form of what they were told!

Twilight gets a ridiculous face, Pinkie becomes depressed, Rarity and AppleJack swap bodies, and Fluttershy turns into a giant pegasus! Twilight goes out of her way to try find the cure for her friends and self, and so leaves the rest of her friends to cope with their problems. Will she and her friends stay like this forever?