Continuity mistake: Dr. Klein and Dr. Taney arrive at the house and go up to Regan's room to see her for themselves. We see inside the room and the two doctors, Chris and Sharon are the only ones there but as they try to give her an injection, Karl appears from out of nowhere restraining her. (00:54:05)????
Continuity mistake: After Chris puts her to sleep and walks down the steps, Willi the maid is cleaning up Regan's mess on the living room carpet from the previous party scene. We saw a nice close-up of the wet carpet as it happened and now Willi is not even close to cleaning the right spot. In fact she's kneeling right on it, yikes. (00:44:20)????