Ned complains to Sean about the plan to identify the immune in America, he wants to repair the sub and head back to England since he believes the cure to be neutralized. He is not a believer that the pandemic was their destiny.
Dr Scott and CDR Chandler debate the Nathan James' course of action -- he plans to pursue the sub, but Rachel points out that they have the only remaining samples of the cure and that they should focus on producing more.
There's no sign of the sub.
The crew on the sub is slacking off, and there's dissension among the ranks.
Alicia tells Rachel that a video came in from her mentor over the satellite. He had an idea to help make the vaccine more effective. He was going to convert the cure into an aerosolized powder. Rachel wants to head to Florida to retreive the data, but Chandler is reluctant. Slattery points out that the men who the virologist had the same accents as the sub captain.
Chandler leads Rachel and the Special Forces Unit into the Florida lab. Everyone has been executed, and all the computer equipment seems to be destroyed. Chandler plans to pursue the men who attacked the lab.
The SFU and Chandler reach the end of the trail at a dock in the Everglades. The Nathan James will provide support as they attempt to track the attackers on fan boats.
Sorensen comes back from exploring a new town, and Ned once again expresses his frustration with the current plan. His brother pulls a knife on him, and Ned does some fast talking to calm Sean down.
The Nathan James has identified a likely destination for Sean and his men. Chandler's team heads out on the fan boats.
Rachel and the new doctor attempt to finish Dr. Hunter's work.
The SFU team splits up to circle the encampment they've found. It seems to be a safe zone, complete with armed guards. Chandler recognizes some of the men from the Solace. Alisha starts to decrypt their radio communications.
Bacon brings Rachel supper, and his description of preparing the perfect roux helps her to have a breakthrough on the aerosolize problem.
Tex blends in to the camp to gather intel. The camp is moving out, and the SFU splits up, with some most members tailing the convoy while Burk, Bivas, and Chandler go undercover on the buses. Chandler sits next to a woman who tells him about Sean and his videos. She tells him that the buses are headed to see him.
Bacon is assisting Rachel and the new doctor, but doesn't understand their science lingo.
Alisha picks up on the subs radio communications, which allows the Nathan James to locate the vessel.
Ned gives the submarine orders contrary to Sean's
The Nathan James figures out that they've located a radio relay and not the Achilles, and they take out the buoy so as to cut off the enemies lines of communication.
As the convoy approaches its destination, Wolf jumps out of the back of a truck. The trucks are splitting off from the busses.
Rachel checks in with Jeter, who is not entirely confident in the mission. She updates him on the progress with the vaccine,, and they discuss building a machine to mass produce the cure.
Tex gets himself and Danny into the compound. Burke and Chandler enter the hotel, and Chandler recognizes Declan's voice as one of the men who killed Dr. Hunter.
Wolf updates the Nathan James on the SFU's progress.
Sean speaks to the crowd, and Chandler recognizes Ned on stage. Sean promotes an American leader for the American immune -- former HUD Secretary Michner, who he claims is the constitutional president.