Zurich, 1950s. Ernst Ostertag, a shy teacher at a girls' school, keeps his homosexuality secret. That is, until his meeting with a magazine editor who's the founder of a small clandestine gay organization called Der Kreis. Through Der Kreis, Ernst gets to know Robi, a charismatic transvestite who's a cabaret star and the two fall in love. At the same time, Zurich is the scene of a series of murders whose perpetrators and victims are all gay. Previously tolerant, the media begins to publish defamatory stories, which turns the justice system and the public against the gay community. While other countries are starting to decriminalize homosexuality, Switzerland tightens the screws.