The series tells the story of FBI agent Emily Byrne (Stana Katic) who, while hunting one of the most notorious serial killers in Boston, disappears without a trace and is pronounced dead. Six years later, she is found in a cabin in the woods, barely surviving and with no recollection of the years she was missing. When she returns home, she finds out that her husband (Patrick Heusinger) has remarried and her son is being raised by another woman. Soon, Emily finds herself involved in a new series of crimes.