Born into a working-class London family, scientist John Samson is committed to fighting for a fairer, more equal world. However, his ideals are put to the test when he becomes entangled with the security services in Weimar Germany, leading to the abrupt end of his Berlin career and his intense relationship with a Jewish Berliner.

As global upheaval shapes his life, John struggles to uphold his values, hurting those closest to him, including the two women he loves. Haunted by guilt over his past, he returns to Berlin after the war, facing new challenges and seeking redemption.

Confronted by a dramatic shift from liberal democracy to authoritarian populism and conflict, John is plunged into a turbulent world with unsettling echoes of today.