Continuity mistake: When Vermeer picks out earrings for his wife to wear, he selects two pearl earrings (same one later found on Griet). When he hands them to his wife, he gives them both to her, however when you look at Vermeer in the next shot he is holding one of the earrings.
Continuity mistake: When Marie is in the back of the van taking the chains of Alex, Alex picks up the knife and it is obviously bent. Once the chains are off and Alex puts the knife up to Marie to defend herself the blade is straight, and stays that way even when "the killer" takes it out of his chest.
Continuity mistake: At one point about halfway through the movie, Jerry Falk sits down in his apartment to translate his thoughts onto his laptop, sort of a mini diary, and the closeup shot of the notebook monitor shows he has typed up over 3 lines worth of text (at 18-point font size setting, no less). Then the next wider shot that includes the laptop screen shows he hasn't finished even the third line; not only that, the text is now in more typical (smaller) font size.
Continuity mistake: One scene is captioned as being the end of the summer, and the kids are going back home for school. The next caption, about ten minutes after that scene, tells us that it is six months later, and also Christmas. But Christmas is just three months after the end of the summer, so either the caption is partially wrong, or the few intervening scenes carried us from September to the following June without even seeing the intervening holiday season, and then the caption was meant to jump us by an additional six months.
Continuity mistake: When Daniel Craig stays out late and, finally, comes home to his wife, he takes his tie off, but doesn't undo the top button of his shirt, but that button, suddenly, is undone.