Truman fights for his life with the President over his lack of leadership in Willoughby. Five days later, upon coming back to Willoughby, XXX tells his men to hit Miles and Monroe's camp. Aaron wonders when he'll get Priscilla back. Charlie finds Miles and brings him back to camp. A massive migration of birds fly over the camp, and Aaron asks if the nano are doing this. She says Aaron should run. A yellow cloud soon begins engulfing the camp - mustard gas. The Patriots complete with gas masks use the mustard gas as cover and begin shooting and killing the residents in the camp. They take shelter in an old tanker truck. The nano is unaffected by the tech even in Priscilla's body.
Monroe decides they need fight fire with fire, and recruits Miles to gain some of the Patriot's mustard gas. Miles goes along much to Rachel's chagrin, and she tells him they're done. After gaining the gas, and Gene recruiting Truman's new wife, Miles takes the gas and Rachel dissipates it using science. Monroe and Connor leave. Miles tells Rachel that she and Charlie pulled him out of that hole, and he's going to try it his own way without Monroe.
Connor and Miles get a new cache of guns and set out on their own. Tom takes Connor hostage, and Monroe bargains for Connor with his own life. Tom mentions that he does not want to kill him, but they do have work to do together.
Finally, the nano makes a call and completes their research: the problem is that it is human nature to burn everything to the ground, and they decided that if they can alter the limbic system in humans to make everyone happy everything will be better for everyone.