How many movies have Aiko Wakatsuki and Toshihiko Masuda collaborated on?

They have worked on 4 movies together! Their first movie together was Go! Anpanman: Star-Spirited Dollie (2006) and was their highest rated movie together. They have not worked together since Lupin the Third vs. Detective Conan: The Movie (2013). They are most known for their animation films together.