Thundergate plot
Robert Wells, an American boy raised in China, goes abroad for his uncle, James Sanderson, to help build a bridge for the Chinese government. Ray Williams, a construction manager secretly employed by Chinese imperialists whose aim is to hinder construction, introduces Wells to a narcotic that causes him to neglect his work. Wells is in a riotous stupor when the wayward son of the Lord of Thundergate meets him by chance and, noticing the striking similarity between them, switches identities with Wells, who as a result becomes involved in a daring conspiracy.