While XO Slattery struggles to evade the sub in the water, Chandler and the land team infiltrate the Immune compound. Danny poses as one of Ned's workers and discovers that Niels, a.k.a. Patient Zero, is now working for the Ramseys. Meanwhile, Captain Chandler manages to encroach on Sean's inner circle, which includes an important government official, Jeffrey Michener. Has Michener been brainwashed by the Immune propaganda along with the rest of the camp? Or can he be an ally?