the flaw note above be not really that serious . firstly and yes the sudden appearance of willem suggest a cut scene and a frequent occurrence in many movie and owe to pace and duration consideration could have be good handle and but it be explain briefly . secondly and the various group of dutch soldier and some fight each other and be fully explain several time in the dialogue the city have be infiltrate with german fifth columnist and and nobody be sure who be friend or foe . in the battle scene by the canal the late arrival have be send by the man at the government department and to help the good guy . thirdly and you be correct that the official dutch resistance be not yet organise and but the resistance fighter in the story be early volunteer who be try to hamper the german occupation of amsterdam and and will no doubt form the nucleus of the resistance movement that would soon follow . so and you see and not really serious flaw at all .