"Something is out there. Something dark, deadly and dangerous, something that won't hesitate to kill you, Twilight Sparkle," Princess Celestia spoke, the alicorn's voice filled with grief. "And no-one is safe from it."

Twilight Sparkle does not have any biological family that she knows of so when she finds a new alicorn that is lost, hungry, cold and thirsty, who does not remember anything from before, she decides to take care of the mare as if she were her sister.