How many movies have Andrew Lau Wai-Keung and Edison Chen collaborated on?

They have worked on 7 movies together! Their first movie together was Dance of a Dream (2001) while their highest rated movie together was Infernal Affairs Trilogy (Chronological Edition) (2006). They have not worked together since Infernal Affairs Trilogy (Chronological Edition) (2006). They are most known for their crime films together.