During the final chase scene, Molly/Angel is using a large-caliber, long-barreled revolver which should chamber a maximum of six shots. She fires six times during the chase. Then the gun is taken away from her and fired a seventh time. There is no indication that she was carrying extra rounds, or stopped to reload if she had.
In any distant shots where Angel is running, she is wearing thick, chunky high heels, as opposed to the stilettos she is wearing in closer, alternate shots when merely walking or standing.
In the beginning montage scene of Los Angeles before Angel's first night. Just 6 minutes in, a quick shot shows the dancing monks in the street. The killer disguised as a bald monk can be seen at the back dancing with them. This doesn't happen towards the end of the movie.
When Angel is studying in the hotel lobby, a hotel employee puts two chairs upside-down on top of a table as he starts to clean up for the night; in the next shot he repeats and starts with the same two chairs again.
When Angel is in the car with the undercover officer, she asks to be let off at the corner where she sees a friend. But in the next scene the friend is seen walking around the corner, so they wouldn't have been visible at the time Angel stated that she saw a friend.
When Angel is studying in the hotel lobby, she is approached by a "customer". Outside, the customer's Buick's license plate is from Quebec and expired in 1977.
It is a mystery as to why Kit would not know that Tom Mix and Hoot Gibson had both been dead since 1940 and 1962, respectively.
As Lt. Andrews and Angel enter her apartment, two crew members are blatantly visible in frame left.