Many people, myself among them, consider Fritz Lang's 1931 film "M" to be his masterpiece; this 2016 film imagines how Lang himself came up with that movie. Mixing real newsreel footage, scenes from the 1931 film and present-day actors re-enacting scenes from Lang's life, this could have been a mess. Instead, it is an absolutely glorious picture about a man who, if Heino Ferch's portrayal of him is accurate, was deeply unpleasant and arrogant - but a genius, nonetheless. I would assume that flashbacks concerning Lang's WWI service, his first marriage and other part of his personal life are based on his real life; I know that Lang, along with much of Germany, Europe and the world, became obsessed with the search for the real Beast of Dusseldorf, as the killer (played both icily and self-pitying here by Samuel Finzi) was known. I would recommend a revisit with the film "M" followed by this film as perhaps the perfect double feature as far as great filmmaking goes. Stunning.