Two police officers, Roli and Ferdinand, control the road users on WIener Höhenstraße. You are literally on the border between town and country.

The Habsburg Dynasty had ruled large parts of Europe and the world for 650 years. During World War I, however, the mighty Austro-Hungarian Empire sowed the seeds of its own demise. At the height of World War I, the world of the Habsburgs was on the brink of collapse. Almost exactly 100 years ago to the day, in April 1918, the most sensitive diplomatic mission of the First World War became a Europe-wide scandal: the so-called "Sixtus Affair". Secret negotiations between the Austrian imperial family and France were supposed to bring peace to the Danube monarchy – and their failure caused the war to escalate and the Habsburgs to fall.

Vienna, 1920. The Austro-Hungarian Empire has collapsed. Peter Perg returns home from the Great War, after years of captivity. But the Vienna he comes home to is nothing like the place he once knew. The new Austrian Republic thrives on social and artistic freedom, but anti-democratic movements and unemployment loom overhead. A stranger in his hometown, his life takes a turn for the worse when one of his former comrades is murdered. Suddenly the mysterious killings of veterans are mounting. Personally connected to the victims, Perg decides to bring the killer to justice. He finds an ally in the cool-headed forensic doctor Theresa Körner, with whom he has a deeper, shared history. Their investigation leads them into the darkest corners of the city, as they confront a brutal and systematic killer and intrigues from within the police force. But when the killer’s net closes around Perg himself, he faces the moral dilemma of his life.