Opening in Russia, the action of the play speedily transports the beholder across Europe and the Atlantic to New York and concerns itself with the theft in St. Petersburg, by a notorious thief, Dou Plou, of the famous Romanoff diamonds from the Count Garbiadoff. The pursuit of these renowned jewels takes the spectator into the palatial homes of the millionaires, and into the underground dens of thieves, into the gold-laden ballrooms of the wealthy, and into the dark alleys, of crime and death. Don Plou, unable to dispose of the stolen jewels in Russia, flees to America. His former sweetheart, Maria Marino, fascinates and marries a wealthy attache of the United States Embassy in St. Petersburg, Mr. Bulford, and with him also comes to America. On his death-bed, Don Plou, repentant and still unable to dispose of the ill-fated jewels because of their world-wide police renown, sends for Mr. Bulford, with the intention of having him restore the stones to their rightful owner, Count Garbiadoff. The crafty Maria intercepts the letter, and hastily going to Don Plou’s lodging, she gets possession of the precious diamonds before the death of her former associate. Consequently, when Bulford, accompanied by a shrewd young detective, Dick Brummage, arrives on the scene, they are greeted by Don Plou’s corpse, and the diamonds are not to be found. Damaging evidence they do find, however, in the form of a package of old letters which Bulford takes home with him. On examining them he finds evidence of his wife’s relations with the dead Don Plou, and suffers an apoplectic stroke while renouncing her. Maria gives him a glass of poisoned wine, and he dies. Instantly Maria manages to fasten suspicion of the crime upon a young clerk, Frank, whom Bulford had quarreled with and discharged. To further suspicion, Maria, with the connivance of her scoundrelly brother, manages to get Frank shanghaied upon a villainous tramp steamer, from which he finally escapes in a small boat. Although the criminals believe themselves safe, detective Brummage has run to earth several clues that lead him to believe that Maria is really the guilty party, and not Frank, who is the brother of Brummage’s fiancée, Mary. Working along these lines, Brummage introduces Mary into Maria’s home as a maid to assist in piling up evidence against the adventuress and her brother. It is not long before Maria attempts to dispose of the diamonds to a certain notorious “fence,” Mother Rosenbaum, who hates Don Plou and his woman accomplice because they betrayed her son to the police in Russia. Mother Rosenbaum has vowed eternal vengeance upon the pair, and learning Maria’s true identity, she is about to avenge herself, when Maria, discovering that Mary is in league with Dick, makes Mother Rosenbaum believe that Mary, and not herself (Maria) is the former accomplice of Don Plou. Accordingly, Mother Rosenbaum decoys Mary to her house on the lower East Side, and imprisons her in the cellar, where she is finally rescued by Dick after a series of most thrilling events. Meanwhile Maria has sought and won the protection of a powerful politician, Senator McSorker, and feeling secure in his patronage, appears at a grand ball at the Senator’s home, brazenly displaying the famous Romanoff jewels. In the midst of the revelry, Maria is suddenly confronted by Dick, who is accompanied not only by Mary and Frank, but also by the Count Garbiadoff, who has just arrived from Russia. Realizing that the end has come, the adventuress swallows poison, and in her death agony rolls headlong down the grand staircase to die at the feet of her accusers. So at last the wonderful diamonds are restored to their rightful owner, and the triumphant Dick Brummage is united to his sweetheart.