Deliberate mistake: As Rosemary is prepared to be raped by the devil she is lying on white sheets. In the next shot as she is being raped she's on black satin sheets. (00:47:30)
Deliberate mistake: When Ben is discussing boarding up the windows to Tom, he says he still needs to get a few spots upstairs. Why would he need to board up the upstairs windows when the zombies have no way of reaching them?