The financier's niece and ward was riding in the park one day when her horse ran away. Casey, the cop, rescued her. Then they found that they knew each other when they were children. The girl visited her grandmother in the country, and "the cop" was "the little boy next door." They drifted apart, but the incident in the park brought them together again, and Casey became a frequent visitor at the banker's home. Some time later the banker became involved in speculations. To carry on his market operations he had utilized the funds entrusted to his care. An unexpected visit of the bank examiners precipitated matters, but the banker, aided by his cashier, so arranged matters that the blame fell upon the policeman's brother. The niece overheard arrangements being made for the teller's arrest, and hurried around to his home to give him warning. Before he could escape the police arrive. The teller tried to escape by the roof, but the sleuths were cunning, and had cut off escape that way before entering by the main door. With escape cut off above and below, the teller was in a dangerous position. The girl was resourceful, however. She bade the man hide in an inner room, saw a book agent in the hall, lured him into the apartment, and when the police dropped in, a few moments later, they arrested the book agent. After they were out of the house the teller escaped. He had explained to the girl that he did not dare surrender, as his own record would be against him, although he swore he was innocent. After he had gone the girl lingered in the flat a few minutes, attracted by a photo of a certain young man, and was there when Casey returned home. She told him what had happened. Before she could get away her uncle arrived with the police captain, intending to question the girl who had tricked the police. The only person to meet them was Casey. The banker wanted to search the place, but Casey refused to permit this, although he permitted the captain to do so. In the inner room the captain found the girl, who hastily told him her story. Then the captain returned to the others, announcing that the suspect was not in the house, and that he had no interest in the girl ("whoever she may be"), for she had not committed any crime. The banker determined to search the house himself. Casey, by a clever ruse, gave the girl a chance to escape. The banker departed, vowing vengeance. After this happening, the girl decided to leave her uncle's home. He had told her that her fortune had been lost. Casey, in whom she confided, decided to try and wrest a confession from the cashier. He made him a prisoner and took him to a tiny island. The cashier finally confessed. Casey saw a way to cinch the case. Soon after the banker received word from the cashier's landlady that when the man disappeared he had left a diary. The banker was shown a diary, which contained entries referring to all of his supposedly hidden crimes. In a panic he agreed to buy it, and when the money had been passed over, the room, heretofore in darkness, was brilliantly lighted, the "landlady" threw off fur wrapper, revealing Casey; while the niece, the cashier, the policeman's brother and the captain came forward from their hiding places. One part of the cashier's confession told of how the girl's fortune had been stolen, and after brief legal proceedings she recovered it. Then she married the policeman.