Sterling is forced to turn to Simon for help when they need an antidote for a fallen leader, unaware that Jarvis is scheming to stop them. Meanwhile, Sean and Vicky try to stop the death of thousands, while Sophia uses Leila to fulfill her goal of mankind's extermination.

Cast: Jason Ritter, Sarah Roemer, Laura Innes, Ian Anthony Dale, Mac Brandt, Sean Carrigan, Alexandra Bokyun Chun, Anthony Nacarato, Ned Vaughn