["M"] is based on the crimes and the final apprehension by the police of the famous child murderer of Düsseldorf. Certainly no subject could be more inherently horrible, more dangerously open to a facile sensationalism of treatment. Yet such are the tact and the genius with which Fritz Lang has handled it that the result is something at once more significant than either the horror story, pure and simple …, or the so-called psychological "document" of the type which Germany has sent us so often in the past. The result is, in fact, a film which answers to most of the demands of classical tragedy. In the first place, Lang has concentrated his interest not on the circumstances but on the social and human consequences of the crimes. We are shown a whole city thrown into panic by what is for every class the least pardonable of all...