Four years after losing her sister Stella, Grace McElroy has begun to heal. She no longer spends her days overcome with grief and guilt. But the appearance of a woman who looks just like Stella makes her doubt her sanity.

Even more terrifying, she learns her adopted daughter's biological father, once a brutal Ecuadorian drug lord, is in the States. Before she can determine whether he's come to reclaim his child, the little girl is kidnapped, and Grace and her family will do anything to get her back.

A hundred miles away, Natalie Burden discovers her estranged father has another family. And Natalie has a sister, Grace Burnette McElroy. The news thrills her, but her mother's debilitating stroke puts her plans to meet her sister on hold.

Her mother's recovery gives Natalie time to follow Grace. She discovers she's not the only one stalking the McElroys. Desperate to protect them, she becomes involved in a fight with a vengeful drug lord.

While Grace struggles to make sense of her ghost-sister, Natalie works behind the scenes to save her niece. Because without Stella's child, there may be no chance of establishing the kind of sister relationship Natalie craves and Grace mourns.