How many movies have Hans Adalbert Schlettow and Rudolf Klein-Rogge acted in together?

They have worked on 7 movies together! Their first movie together was Dr. Mabuse, the Gambler: Part 1 – The Great Gambler (1922) while their highest rated movie together was Die Nibelungen: Siegfried (1924). They have not worked together since Menschen vom Varieté (1939). They are most known for their crime films together.