How many movies have Halina Tam Siu-Wan and Tong Ka-Fai acted in together?

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 9 (2001). They have not worked together since Troublesome Night 11 (2001). They are most known for their horror films together.