As a child, Olivia Dunham is “Subject 13,” exposed to the experimental drug Cortexiphan. It has strange effects upon her—effects that manifest when her stepfather assaults her mother—with dire consequences.

All of her life, Olivia hides the strange things Cortexiphan has done to her. But the older she gets, the more difficult it becomes to suppress them. And when faced with a life-or-death situation, she can no longer deny her true nature. For if she does, someone close to her will die.