How many movies have Ryoichi Sato and Yuu Tokui collaborated on?

They have worked on 7 movies together! Their first movie together was Detective Ushio VS Case Reporter Saeko at the Terminal Station (2008) while their highest rated movie together was Taxi Driver's Mystery Diary 37 - Mystery of Double Homicides from Tokyo to Hamamatsu (2015). They have not worked together since Detective Ushio vs. Case Writer Saeko: Last Family (2017). They are most known for their mystery films together.