How many movies have Onno Molenkamp and Youp van 't Hek acted in together?

They have worked on 1 movie together! Their first movie together was Youp van 't Hek: Tunnel zonder vluchtstrook (1986) and was their highest rated movie together. They have not worked together since Youp van 't Hek: Tunnel zonder vluchtstrook (1986).