Frank attempts to save his team, and pays the price; at the same time, the wives get creative trying to make life on the Hill more interesting.

Frank clashes with Charlie to protect Babbit, who has become the subject of an investigation.

Frank seeks medical answers; Charlie and Helen travel to survey an off-site reactor.

A development overseas re-invigorates the hunt for a spy on The Hill. Charlie and Abby make a sacrifice when the plan with Frank is threatened.

Frank is offered a life-changing opportunity. At the same time, the U.S. Army put Charlie on the hot seat.

Charlie is forced into a new leadership role in the race to build the world’s first atomic bomb.

Frank discovers the real reason he's been taken captive.

The scientists and the Army battle for control of the bomb.