The series tells the story of FBI agent Emily Byrne (Stana Katic) who disappears without a trace while hunting one of Boston's most notorious serial killers, and she is declared dead in absentia. Six years later, she is found in a cabin in the woods, barely alive and with no memory of the years that she was missing. She returns home to learn that her husband has remarried and her son is being raised by the new wife, and she soon finds herself implicated in a new series of murders.