Series 4 is set in 1930s Berlin, just after the Golden Twenties culminated in the global stock market crash and the Great Depression – and the Nazis' march to power is in full swing.
The story centres on detective Gereon Rath (Volker Bruch), and his ambitious colleague Charlotte Ritter (Liv Lisa Fries). As Gereon’s investigations lead him into the boxing milieu – and politically, uncomfortably close to Hitler’s militant supporters – Charlotte risks her job to help her homeless sister, who roams the streets of Berlin with a group of young peers, fighting for survival.