A fictional biography of media magnate Charles Foster Kane (Orson Welles) - a thinly veiled William Randolph Hearst that brought Welles and RKO all kinds of problems - that recreates a life in flashback, Welles' "Citizen Kane" was a startling cinematic debut by any standards, and from a 25-year-old made it nothing short of remarkable.
Beginning with Kane's lonely death at his crumbling and ornate Xanadu mansion, the film details the destruction of Kane's childhood when his mother unwittingly inherits a legacy and his resulting adolescent realisation that part of the legacy includes a newspaper, which Kane decides to run personally. From there, Kane builds a media empire, dabbles in politics and women, and eventually starts to alienate all those around him.
A potent metaphor for the betrayal of principles, the souring of the American Dream, and an intelligent mediation on the corrupting nature of power, the film's reputation is nothing short of gargantuan. Regularly cited as the greatest movie ever made, there's no doubting its pure brilliance and status as a contender for so lofty a claim.
What is beyond doubt is that Welles and his collaborative troupe of Herman J Mankiewicz (screenplay), Gregg Toland (photography), Robert Wise (editor), and the fantastic cast of leading players managed to invent a whole new cinematic vocabulary. The attention to detail (ceilinged sets, the meticulous creation of Xanadu) and technical brilliance (deep focus photography and hitherto unchartered camera angles) combined to influence the future of cinema. "Citizen Kane" is the margin by which all of Welles' later efforts came to be judged and also, in many ways, the benchmark of film production.