Continuity mistake: The first time we see the young doctor doing his "lobotomy" in London Hospital (to the girl that was married to Prince Edward), Ian Holm comments on the procedure for some guest as they stand behind a glass window. You can clearly see the young doctor doing the third strike with his hammer in a reflection in the window. The movie cuts back to the young doctor and he is doing the third strike for a second time.
Factual error: The scene including the appearance of Joseph Merrick is not correct. The scene shows us Frederick Treves presenting John Merrick to the other doctors. He calls Merrick 'Joseph', but someone corrects him that he should call him 'John'. That is not correct: in real life Treves was the only one who instantly called him John, while his real name is Joseph.
Question: In the middle of the movie, one of the doctors tells the others of John Merrick, aka The Elephant Man. They show him for a few seconds Disrobed.. What is the point of showing Merrick in the movie? This scene seems totally isolated from the rest of the plot. It almost feels like they had an extra minute to kill and decided to add it in.
Question: Why is it a "known fact" that Mary Kelley was killed by Jack the Ripper? Her murder differs in many ways from the others. She was killed indoors, she wasn't wearing any clothes, her body was so savaged that she was unrecognisable. The other murders took place outdoors with victims fully dressed and only partly savaged. Considering the number of violent deaths that took place in London at this time (most of them by slashing the throat) she could have been murdered by anybody. I know Abberline was called to the scene of the crime but that doesn't prove the Ripper actually did it and Abberline was called to more murder scenes than just the five official Ripper ones. What makes people so sure that Jack the Ripper killed Mary Kelley?