How many movies have Atsushi Watanabe and Iwaji Hiraoka collaborated on?

They have worked on 4 movies together! Their first movie together was 音楽大進軍 (1943) while their highest rated movie together was The Way of Drama (1944). They have not worked together since 娘十八びっくり天国 (1952). They are most known for their drama films together.