Bellamy struggles to keep Jacob safe from outside forces. But a tragic incident from his past as a cop continues to haunt him. Elaine is pressured to find out where dad Caleb hid the stolen bank money before the FBI comes to town and learns the truth about Arcadia. Maggie delivers shocking news to Rachael, and Caleb gives Bellamy a chilling warning.

With the help of Bellamy and Sheriff Fred, Tom leads the charge in the search for Rachael, but her situation becomes increasingly dire as her captors grow more desperate. Maggie and Dr. Ward continue their medical research on the resurrected subjects and a series of shocking discoveries sets them on the brink of a game changing find, however, their focus shifts when Arcadia is suddenly in the throes of an epidemic.