When Blake, Duke of Welminster arrived in St. Petersburg to discuss the news of Napoleon's advance on Moscow. At that point, love is the furthest thing from his mind! Then, invited to the home of an old friend, Princess Sonia, the duke realizes that the princess sees him as a potential husband for her daughter, Tania. But as Tania and a young friend dance for him, it is the friend, Zoia, and not Tania, who captures his attention. Zoia is a beguiling young woman whose mother fell into disgrace by marrying beneath her station, and whose father, a French musician, still lives in the threatened city of Moscow. Suddenly, mystically, the duke finds himself under her spell.