How many movies have Kim Chung-gi and Yang Dong-Wuk collaborated on?

They have worked on 5 movies together! Their first movie together was Thunderhawk From Outer Space (1986) while their highest rated movie together was Thunderhawk 3 - Thunderhawk From Outer Space Blitzkrieg (1987). They have not worked together since Thunderhawk 5 - New Machine Thunderhawk (1988). They are most known for their family films together.