Continuity mistake: The train that Carol takes from Washington to Baltimore is an Amtrak Acela Express train, as can be seen in the station and interior shots. The exterior shot of the train passing by shows a different type of Amtrak train.
Continuity mistake: When Dr. Bennell receives a phone call from her now alien-overtaken ex husband at the beginning of the movie she's in her office. She is paged by her secretary and is wearing different clothes than the next scene showing her in different attire, getting into her co worker's car, going to work, and then explaining to Craig about her unpleasant ex husband's call. It appears she must have received the call at home, but was shown receiving the call at her office.