When Gail Gunnerson was six years old, a Thing came to her bedroom door. It was so horrifying a sight, so dreadful in its implications, that the slender threads of reality were snapped. Now, twenty years of healing Time have passed. The specter of her childhood is forgotten, buried so deeply within her mind that seemingly no therapy, no drug, no traumatic shock can bring it forth again. Total, merciful amnesia protects her. But then: her very life depends upon restoring that memory.