In 1975, legendary jazz pianist Keith Jarrett — one of the biggest names on the cult label ECM — played a concert in Cologne, Germany that would be hailed as one of the greatest live recordings and would become the top-selling piano record in history. But the concert itself, put together by a single tenacious 18-year-old, almost didn’t happen. Köln 75 follows youngster Vera Brandes (Mala Emde) as she zips around the West German city, promoting jazz to strangers who think the art form dead and scrambling to get the concert going.