How many movies have Hisashi Saito and Kouichi Arai collaborated on?

They have worked on 4 movies together! Their first movie together was Digimon Adventure 02: Hurricane Touchdown! The Golden Digimentals (2000) while their highest rated movie together was Cowboy Bebop: The Movie (2001). They have not worked together since Naruto the Movie: Ninja Clash in the Land of Snow (2004). They are most known for their animation films together.