One cold autumn night, Twilight Sparkle lets in a pale and weary traveler into her home. When she accidentally discovers his dark secret, she is assaulted by him, and is left to die... When she woke up, she finds that she has been turned into a Vampire, an ancient enemy of Equestria last seen during Nightmare Moon's Rebellion. She now walks the thin line between life and death, sustained only by the blood of others.

Her friends now race against time to find a cure for this ancient curse, and stop the Vampire who infected Twilight, before he can create a new army of Vampires to conquer Equestria. Otherwise, Twilight will join the forces of evil and darkness, as the Bride for the Lord of Vampires. They have to work quickly, as every day passes, Twilight's thirst for her friends' blood increases...