How many movies have Gus Backus and Helga Billian collaborated on?

They have worked on 2 movies together! Their first movie together was Mein Schatz, komm mit ans blaue Meer (1959) while their highest rated movie together was Tausend Takte Übermut (1965). They have not worked together since Tausend Takte Übermut (1965).