It is hard to identify the true genre of M for several different reasons. First off, the film was created before genre conventions were established. Thus, as a result, many different scenes have different vibes and style that is not modern conventional genres (Horror, comedy, etc). The film also lacks a soundtrack that would help establish the mood of the film. Some would argue that it is a horror film because the film is about a serial killer. However, I disagree with this label because the film does not revolve around the children's and mothers' point of view. It does not try to invoke the same fear and suspense that the characters experience in the film. Some also label it as a melodrama. I also disagree with this because the film does not emphasize the emotions of the characters. You dont feel any personal connection to any particular character in the film. Rather, the film tells a story that involves many different characters with different intentions. It is for this reason that the film, in my opinion, is a criticism on society as a whole, not on any particular individual. The ending is the pinnacle example of this theme, where the killer argues that at least he isn't lazy and selfish like the other criminals. That it is beyond his control. Even when the lawyer argues it is unlawful to kill him, the crowd of criminals rush towards him to kill him anyway. Pretty decent movie overall, although I felt some parts dragged on for too long. If I were to see this movie back when it was released, however, I dont know if I would have had that opinion considering its one of the first movies ever. 3/5 in my modern eye.