How many movies have Du Yiheng and Francis Nam collaborated on?

They have worked on 4 movies together! Their first movie together was Detective Dee: The Blood Tree of Chiyou (2018) while their highest rated movie together was Detective Dee: Solitary Skies Killer (2020). They have not worked together since Detective Dee: Solitary Skies Killer (2020). They are most known for their action films together.