Rainbow Dash has an exciting life in Ponyville. She's on the weather team as well as a Wonderbolt and is one of the legendary Mane Six ponies. Her life is both exhilarating and happy. But, lately, she's had a problem... Sometimes, late at night, she will kill a random pony, for no reason, and then hide the corpse... She doesn't know why she's now a serial killer, but she just does these things... Unable to find answers and not sure where to turn, she decides to enlist the help of Rarity to break this mysterious curse.