7. Leon
This one really surprised me when I discovered it a couple of months back. The film is about an elite assassin (Jean Reno) working in New York City who takes young Matilda (Natalie Portman) under his wing after her family is murdered by a corrupt cop (Gary Oldman). Leon is one of the best films of the 90s, chock full of over the top action and an engaging central relationship. Yet all over the Internet it's been called Leon: The Professional. This title isnt just a one region change either; nearly every country outside of its native France, the UK and select parts or Europe has this title. The alternate title is a mouthful and attempts to give an unnecessary sense of intrigue to the film. Did the marketing department assume people would think it was about the French city Lyon, not an assassin? Or were a couple of English words needed in the title to ensure audiences didnt think they were walking into a foreign film? There are a few cases of title changes to work in different territories, but this one makes the least sense.