Plot

Robert Wells, an American youth who was reared in China, goes abroad for his uncle, James Sanderson, to assist in the construction of a bridge for the Chinese Government. Ray Williams, construction manager secretly employed by Chinese imperialists whose aim is to impede construction, introduces Wells to a narcotic that when taken causes him to neglect his work. Wells is in a dissolute stupor when the wayward son of the Lord of Thundergate meets him by chance and, noting the striking resemblance between them, exchanges identities with Wells, who as a result becomes involved in a daring conspiracy culminating in romance with a Chinese-reared white girl and in his own physical rehabilitation.—AFI

Robert Wells, born in China and acquainted with the language and customs, is sent by his uncle, James Sanderson, to assist in the construction of bridges for the Chinese government. But Imperialists, opposed to the construction, bribe Ray Williams, the manager of the company, to delay the work. Williams plans to disgrace Wells in the eyes of Sanderson. In addition, Williams is in love with Alberta Hayward, Sanderson's ward, so he hopes to gain access to the Sanderson fortune. Williams plies Wells with liquor, which causes Wells to sink lower and lower and finally disappear. Sanderson goes to China to search for him. Kong Sue, son of the Lord of Thundergate, steals money from his father's safe and bargains with the priests at the temple for Ellen Ainsmith, a white girl who has been reared as Chinese. The Lord of Thundergate sends guards after his son. Kong Sue hides in a disreputable establishment. There, Wells gets into a drunken brawl. Wells is knocked unconscious. Kong Sue notices a remarkable resemblance to Wells. Unknown to both men, they are half-brothers. Kong Sue changes clothes with the unconscious Wells. When the guards arrive, they take Wells to the palace, believing he is Kong Sue. A coolie, whose wife was disgraced by Kong Sue, recognizes the real Kong Sue, imprisons him and lashes him with a whip. The Lord of Thundergate dies suddenly and Wells, who is still believed to be Kong Sue, is proclaimed the new Lord of Thundergate. Ellen is brought from the temple, as his bride. Seeing she is white, Wells continues the masquerade in order to protect the girl. Then Wells discovers proof that Williams is being paid off by the Imperialists. Wells reveals his true identity and exposes Williams in front of Sanderson. Kong Sue escapes, and annuls his marriage to Ellen. This clears the way for Wells and Ellen to marry.