How many movies have Edmond Yuen Chi-Keung and Jeff Kam Chun-Man collaborated on?

They have worked on 3 movies together! Their first movie together was Troublesome Night 8 (2001) while their highest rated movie together was Troublesome Night 10 (2001). They have not worked together since Deadly Camp 2003 (2003). They are most known for their horror films together.