Grand Duke Ludwig of Saxe-Thalberg is detained in New York with his aide and is unable to use his money until it is released by the German government. In order to survive, Ludwig gets a job working for Gordon, whom he believes is wealthy, but who is actually a jewel thief. Gordon tells him to have a black pearl matched by Wallington's Jewelers. Ludwig leaves the pearl there, and unknown to him, Gordon sells the jewelers an exact match for a high price. Gordon, his gang and his moll Sally, rob Wallington's Jewelers of the black pearls. Angela, who works at Wallington's, uncovers Gordon's scheme and warns Ludwig that he is being used. He fights with Gordon and then returns to the store to confess his involvement. Angela arrives at the store with the police, Gordon and Sally. When Angela suggests arresting Ludwig as an accomplice, a call to the German embassy reveals that Ludwig is a millionaire, and he is released. Ludwig buys one of the black pearls as a present for Angela, and she reciprocates with her love.