M. de Sadre is one of the armourers for the police force who supplies weapons for Van Helsinki in the fanfiction Van Helsinki: Before the Case, and is mentioned in Van Helsinki: First Case. He is described as one of those men who always looked as if someone had rammed a poker up their backsides moments before, and they were not only forced to remain ramrod straight upright, but also disliked walking about. Sadre is described as having adopted a 'waddle-walk' to compensate. In First Case, Van claims that dee Sadre said Van had 'some natural talent' in shooting. In Before the Case, he gives Van a CZ75 pistol and a hammerless Makarov, and seems educated about weaponry, as befits an armourer. Sadre also forces Van to hand over his Glock 27, saying that it is traceable to Van directly. Van remarks to himself that he always feels patronised by de Sadre, though he admits the man is useful.