Character mistake: In one of the National Tattler headlines, the word "pursues" is misspelled "persues". (00:52:15)
Character mistake: When the undercover cop says, "Hi, when was the last time you had a good..." she doesn't identify herself as a police officer. (00:37:15)
Character mistake: In the morgue, the Captain says the latest victim brings the total up to 16. However, prior to the killing, the news report said there's been 16 victims. This is the 17th victim.
Character mistake: When William finds the footprints on the ground after the body is found in the blood vat, he tells Adso that they were twice as deep as they should've been because the person who made them was weighed down by the weight of a body. Adso points out that the footprints were going away from the vats, to which William rebukes him and says that the man who made the prints was possibly dragging the body. If that was so, the footprints would not have been so deep, as the person moving the body would not have been weighed down nearly as much by dragging one along the ground. William is a learned investigator who shouldn't have made such an obvious mistake.