How many movies have Martijn Westerholt and Robert Westerholt acted in together?

They have worked on 2 movies together! Their first movie together was Within Temptation - Mother Earth (2002) while their highest rated movie together was Within Temptation: Let Us Burn Elements & Hydra Live in Concert (2014). They have not worked together since Within Temptation: Let Us Burn Elements & Hydra Live in Concert (2014).