After months of dead ends, the Evans family receives information that could finally lead them to Piper. While Jo and Brooks follow this new lead, Ed helps Mia as she tries to send Piper a message. Meanwhile, Alex and Chris stumble upon a mysterious shipment in the harbor.
After Jo, a police chief, takes in a young child she finds near the site of a mysterious accident, she soon discovers the girl has no memory of what has happened or who she is. The investigation into the history that led up to the the accident - and questions as to how and why it happened - draws the woman into a conspiracy larger than she ever imagined, with the child's identity at the center of it.