A psychopathic murderer of children evades the police but is caught by the city's criminals.
Dominated by the peerless performance of Peter Lorre as the child killer apprehended by the law and the underworld, M not only makes a powerful case against capital punishment, but was also one of the first features to focus on forensic policing.
Several missing scenes have been restored here, but it's not simply a case of re-inserting lost snippets. This 105-minute version (which must now be considered the definitive take) also removes the music that was added for the 1960 reissue, and so recaptures the atmospheric silences that director Fritz Lang boldly insisted upon at a time when most other newcomers to sound were bombarding viewers with audio effects.
Undiminished in dramatic power and cinematic ingenuity - and still chillingly contemporary in its theme - this film remains an unqualified masterpiece.
Part social melodrama and part satire this film is an undeniable classic.