This dramatized short film describes the historical mystery of France's "man in the iron mask". King Louis XIV imprisoned a man who was never identified, but who was forced to wear an iron mask for the length of his captivity, which ended only in his death. Several candidates for the identity of the man are investigated.

G-Man Charles Bent Martin is sent out to break up a nationwide racket. A transport company is aiding fugitives making a getaway in exchange for the lion's share of their loot. Through an old friend, whom he once barnstormed in an air circus, Martin joins the gang as a pilot. He becomes interested in Carol Butler, a beautiful girl involved with the gang through the activities of her ne'er-do-well father.

It is the fate of a small frontier town, adjoining the no-man's-land where the Russians and Austrians are fighting out one of the final campaigns of World War I, to be occupied one day by the Russians, the next by the Austrians, and the inhabitants soon acquire a complacent view of the changing allegiances. To the town comes Ann Warschaska, intent on avenging the suicide of her sister, who has killed herself after being betrayed by an Austrian officer. She knows no more about his identity than the number of his room at the "Hotel Imperial".

Drummond's wedding with Phyllis is interrupted when the inspector guarding their gifts is killed. He tries to trace the killers and uncovers the mystery of diamond counterfeiters.

A Chinese-American woman tries to expose an illegal alien smuggling ring.

Racketeer Steve Recka, art patron and political power-maker, rules his town and Madame Lan Ying, his beautiful friend and hostess (read:mistress), with an iron hand. He meets Margaret Van Kase, a socialite not impressed by his power nor his wealth, having no money herself, and Steve makes frantic efforts to win her and turns away from the loyal Lin Yang.