Orphaned and poverty-stricken, Gilda is amazed when her sister Heloise arrives unexpectedly, for Heloise has been living in London with her wealthy Godmother and scheming for the hand of the Marquis of Staverton. Then suddenly Heloise dies of an overdose of laudanum. Gilda decides to impersonate her sister and seek help from Heloise's Godmother. But Gilda herself falls under the spell of the handsome Marquis, and discovers that Heloise had been involved in something treacherous ..