How many movies have Hiroyuki Kawasaki and Mankichi Maeda collaborated on?

They have worked on 8 movies together! Their first movie together was 隠密くノ一忍法帳 餓鬼姉妹 (2005) while their highest rated movie together was Lady Ninja Kasumi 3: Secret Skills (2006). They have not worked together since Judo Girls (2014). They are most known for their action films together.