And she was

When Brenna Spector was a child, her older sister stepped into a strange car never to be seen again. This traumatic event triggered in Brenda a rare neurological disorder that enables her to recall every detail of every day of her life, except - cruelly - that dark day when her sister disappeared. Nowadays Brenna puts her unusual skill to use as a missing persons investigator and it's while she's trying to find local woman Carol Wentz that she discovers connections to another child's disappearance, ten years earlier. Before too long a link to her own past emerges. Could this be the answer she's been hunting for all these years?