 Eric Sanderson wakes up with no memory of who he is or any past experiences.He is told by a psychologist that he has a dissociative condition known as fugue but a trail of written clues purporting to be from his pre-amnesiac self describe a more fantastic and sinister explanation for his lack of memories.According to these, he has activated a "conceptual shark" called a Ludovician which "feeds on human memories and the intrinsic sense of self" and is relentlessly pursuing him and will eventually erase his personality completely.