
Continuity mistake: In the Shrieking Shack, Harry grabs Sirius Black and throws him to the floor. There are many black marks on the floorboards, like paw prints etc. Although Sirius doesn't move when Harry first throws him on the floor, the black marks on the floorboard near Black's head change between the first wideshot of him on the floor and the following closeup and in subsequent shots as well. (01:27:25)