When retired merchant J. T. Manly is murdered, his son James, with whom he had quarreled, is arrested and finally convicted through the testimony of Manly's valet Aguinaldo. Shortly before James's execution, Sidney Holmes reveals to retired criminologist Martin Cross that on the night of the murder, he saw Aguinaldo commit the crime

Lillian Hill, a poor stenographer, sacrifices her romance with an equally poor playwright, Henry Parker, to marry her boss Wilbur Mason. She does this only so that she will have the means to pay for surgery to restore her mother's sight. But the surgery is unsuccessful, and her coldness towards Mason arouses his jealousy.

Russian brothers Count Boris and Alexis Rabourdin obtain a Japanese coastline defense map and plan to sell it to German agents in London. In America, Alexis schemes to marry wealthy Eve Bertram, who loves him. Boris, meanwhile, falls in love with Christine Lesley, Eve's neighbor whom Eve's brother Guy, an amateur inventor experimenting with explosives, also loves.

A psychological study of the effects of drug addiction on humanity. Helene Ford has been injected with heroin by an unscrupulous physician, causing her to act irrationally. Her husband Stephen, a noted artist, hires a model whom Helene, inflamed by their friend Jack Murray, suspects of having an affair with Stephen. The model is also addicted to drugs and convinces Stephen to try heroin to forget his troubles. Both Stephen and Helene then become addicted to drugs. They abandon their home and then separate, after which Stephen resorts to crime to support his heroin addiction. During an escape from the police after a robbery, Stephen encounters Helene again, this time near death. She sacrifices her own life to shield her husband, but Stephen and his former model plunge to their deaths.