Continuity mistake: In the scene near the end where Graham and his son are trapped in the bedroom, the Red Dragon attempts to break down the door. After many forceful attempts, we see parts of the door jamb and moulding break-away and stick out from the wall. However, when Mrs. Graham enters the room after the shootout, the door jamb and moulding are in perfect condition.
Continuity mistake: Before they reveal the face of the Red Dragon, they show him flipping through his book of newsclippings. He focuses on the face of the Tattler reporter and puts red markings through his face. When they show him closing the book, you can clearly see the face and the markings are noticeably different in the wide shot from the close up.
Continuity mistake: When Graham and Hannibal are talking for the first time, Hannibal walks right up to the glass wall and there is a close up of his face from Grahams side of the glass. You can see that there is no reflection of Graham on it, thus meaning that there is no glass wall there in between Hannibal and Graham. This happens frequently through out the movie.
Continuity mistake: Anthony Hopkins starts the film with a conservative mid-Atlantic accent that requires no heavy acting. When he is talking to Will Graham in the cell phone, he changes to a ridiculously broad Georgia drawl, even when he isn't doing "funny voices." How he manages to fit either of these in as a Lithuanian of Italian descent is anyone's guess.
Continuity mistake: In the scene right before Freddy Lounds is abducted by Dolarhyde, he is driving his car back to the garage of the newspaper he works for. In the scene of him pulling into the garage, he has half his arm hanging out of the rolled down window, then in the very next shot the window is rolled all the way up.