Dr. Mabuse: The Gambler is the eight-reel version of Fritz Lang's twenty reeler, two-part silent thriller, Dr. Mabuse. Mabuse (Rudolph Klein-Rogge) a sinister mesmerist/psychiatrist, toys with the weaknesses of the rich and influential. He worms his way into the confidence of wealthy men, plays cards with them, hypnotizes them into cheating at their businesses, then puts them in a position to be blackmailed so that he can corner the stock market. A devilishly ingenious plan-but Mabuse is up against the plodding, methodical police detective Wrenk, whose subconscious is not so easily swayed...at least, not at first. In 1932, Lang directed a talkie sequel to Dr. Mabuse the Gambler, The Testament of Dr. Mabuse.
by Hal Erickson synopsis