After the horrifying revelations and reversals of fortune in Baltimore, Chandler and his fractured team join forces with an underground resistance in an attempt to defeat Amy Granderson. With doses of the cure running low, Rachel tries to do some good for the sick while remaining a prisoner at Avocet. Meanwhile, Slattery and the crew of Nathan James are in a race against time to save an injured Dr. Tophet and regain control of their ship.

With their mission now fully dedicated to spreading the cure, Nathan James puts a call out to civilians to meet at pre-selected ports across the country.

Sixteen months after thwarting the coup in America, Nathan James must face yet another global disaster. The question remains, where in the world is Tom Chandler?

Having lost their only lead, the crew of Nathan James continues their search for an item that could save the world. Chandler immerses himself in a mission for revenge.

Nathan James is diverted from their mission when they receive a suspicious distress call from a fishing trawler.

The search continues with a reconnaissance mission but things turn violent when an old foe resurfaces.