When British scientists, who have done extensive work on an Implosion model similar to Frank’s, visit The Hill, Frank gains some unsettling perspective. Charlie grapples with whether to tell Akley about the revelation he made about Plutonium, as well... (more) as his fate with their group. As Charlie and Frank both face grim predictions about the future of their prototypes, the stakes at home are raised when Abby discovers what is really happening to the Jews in Europe.