How many movies have Aki Yokoyama and Ikue Otani collaborated on?

They have worked on 6 movies together! Their first movie together was Detective Conan: Sunflowers of Inferno (2015) while their highest rated movie together was Detective Conan: Episode One - The Great Detective Turned Small (2016). They have not worked together since Case Closed: The Fist of Blue Sapphire (2019). They are most known for their mystery films together.