Joseph Losey's M, 1951

Losey spent most of his career on commissioned projects that mixed melodrama with social significance.
-- Andrew Sarris

M was the last movie that Losey made in America; he was a victim of the House Committee on Un-American activities not because he was blacklisted or jailed but because America lost an effective observer and critic when Losey fled to Europe.  M,  a remake of Fritz Lang's art house favorite of the same name, from 1931, feels like Losey was just beginning to accomplish something.

M has a very modern feel, as parents are afraid for their children, with a child-murderer loose in Los Angeles whom the cops can't find, concerned as they are with using rubber hoses on suspects.  Many citizens are acting as vigilantes, beating up any adult they see with a kid, the adult usually turning out to be a parent.  In a nice piece of irony the child-murderer is caught by a syndicate of criminals, their gambling and vice rings being hampered by police harassment.  The murderer is finally identified by a blind man, who sells a balloon to the same man playing a penny whistle who had bought a balloon for a girl who was murdered. The murderer is chased into the Bradbury Building (used effectively in a number of other films of the period, including D.O.A.in 1950) and put on "trial" by the criminals and relatives of the victims.  The murderer begs to be punished for what he could not help doing but is left lying on the floor for the cops to pick up, receiving more sympathy from the criminals than from law enforcement that doesn't care about his illness.

Losey uses the Bunker Hill neighborhood of Los Angeles for locations, a neighborhood of both families and loners, who live in old and decaying Victorian homes (director Robert Aldrich was an assistant on Losey's film and used the same location effectively in Kiss Me Deadly, 1955).  The kids and minorities don't have a lot to do but jump to follow and help identify the murderer.  It is as true now as it was then that the mentally disturbed do not get the help they need and this lack of help leads to tragedies, as Losey shows a table set for dinner while a mother searches the neighborhood for her missing child.