A Lord's son loves the daughter of a counterfeiter who steals necklaces.

Joseph Parker, an American, who is living with his daughter Eve at a stylish London hotel, is under suspicion at Scotland Yard, where it is thought that he is in some way connected with the counterfeiting that is going on. Cullen, the most capable of all men at the Yard, is sent out on the case. But the task of getting the criminal is not as simple as it seems, for "Smiling" Parker is clever and his daughter has attracted the attention of Paul Walmsley, an aristocrat of high family. Parker is in a deal with the counterfeiters, which Cullen discovers. He traces them to the rendezvous, but there Parker gives him the slip. But Cullen knows that Parker must have some of the counterfeit notes on his person, so he follows him to the hotel. At the hotel Paul is dining with Eve. Parker sees Cullen coming and slips the money into the pocket of the waiter and there is nothing found on him. Cullen is again baffled. In the meantime Paul proposes to Eve. But old Parker says that they are crooks and if Paul wants to marry Eve he must become one of them. Paul agrees and they plan a scoop. The object of their endeavors is a pearl necklace, and they even go so far as to warn Scotland Yard of their intentions. On the evening of the robbery Parker, Paul and Eve get seats at the opera directly behind the woman with the pearls. The police are watching, but nothing happens until the opera is all over. Then the pearls are taken by a strange man whom the detectives arrest as soon as he leaves the theater. But when they get him to the police station they find that he in turn has been robbed of the jewels by Parker. Cullen rushes after the American and once more takes him into custody. But this time Parker slips the necklace into the pocket of Cullen himself and a search of the party proves futile. The next morning Paul is astounded to find the necklace in his own pocket, an incident which was done by Parker. The next day, when Paul is presenting Parker and Eve to his father, Parker accidentally makes a slip and says that his name is Bundercombe. Cullen hears this and wires to America for information about that name. At this time Parker receives a note saying that he can get some more of the counterfeit notes at a certain address. He is followed to the address by Paul and Eve, and also by Cullen and his men. When Parker arrives he is astounded to find that the men he has to deal with are none other than those whom he betrayed to the police. They attack him and throw him into the cellar with a lot of rats. Eve and Paul go for the police. They meet Cullen and his men, who come to the rescue. Parker smilingly gets the whole crowd out of the scrape, explaining away the whole matter as a joke. At last the report comes from America that a man is wanted for the murder of a millionaire by the name of Bundercombe, who has mysteriously disappeared. Cullen now has something that he can arrest Parker for and proceeds to warn Paul that he had better get out of the mess. Paul balks at the idea of being mixed up with a murderer, so he and Cullen go to arrest Parker. But when they arrive Parker says that he is Bundercombe and tells the story of how he ran away with his daughter to escape the wrath of his wife, a suffragette. To cap the climax, Mrs. Bundercombe arrives to claim her hubby. So Cullen arrests the man to enable him to escape from the irate woman, and the picture ends happily as the lovers marry and Bundercombe succeeds in ridding himself of his troublesome helpmate.—Moving Picture World synopsis