The summer is ending. Samuel learns the truth about the Shaws and the MI5 men. He is invited to an extraordinary secret meeting, while Hannah becomes increasingly worried about her father’s safety, and David continues to deny he is Kathleen’s son.

In this drama series set in Britain during the late 1950s, Samuel, a Russian-born Jewish inventor, is tasked to use his technological expertise for a secret mission by MI5. Following the advent of the space race and the first hydrogen bomb test, he and his family get caught up in the tensions of the Cold War.