Brilliantly played with flamboyant dastardliness by Rudolf Klein-Rogge, psychoanalyst Dr Mabuse is a criminal mastermind, whose genius for hypnotism and disguise enable him to defraud the Stock Exchange, steal treaties, run crooked gambling dens, abduct women and murder anyone who stands in his way. Yet, when he's finally brought to book, he disintegrates into insanity.
As is clear from the subtitles appended to each episode - The Great Gambler: A Portrait of the Age and Inferno: A Play About People of Our Time - Fritz Lang and his co-scenarist and wife-to-be Thea von Harbou (who had just divorced Klein-Rogge) intended this epic thriller to be a condemnation of Weimar decadence and amorality and contemporary critics lauded its exposé of societal excess.
Yet theorist Siegfried Kracauer could later suggest that the film anticipated the nation's seduction by a similarly mesmeric malevolent, Adolf Hitler, who masked his crimes with a cloak of political expediency. It certainly shared the brooding atmosphere of another Expressionist classic that Kracauer claimed prepared the German psyche for tyranny, Robert Wiene's The Cabinet of Dr Caligari, whose theme of malleable madness would recur in the 1932 sequel, The Testament of Dr Mabuse, in which the maniacal villain grooms asylum director Dr Baum (Oscar Beregi) as his alter ego.
However, by the time he produced a third installment, The Thousand Eyes of Dr Mabuse in 1960 (in which a madman claims to be a reincarnation of the fiend and turns out to be his son), Lang was no longer able to temper his melodramatic instincts with the visual authority he had displayed in the original, where the use of lighting effects, décor and multiple exposures was unerring and masterly.
Yet Lang still occasionally succumbs to excess here and there are sluggish passages filled with interminable intertitles. But, overall, the plotting is assuredly mature and far less serialised than it was in his earlier two-parter, The Spiders.