It was Lieutenant McElroy's extreme devotion to his younger brother, Dr. Edward McElroy, which really provoked the quarrel between the two. When the doctor fell in love with Julia, the fair daughter of the fashionable Mrs. Vantine, whom the Lieutenant identified as "Slick Kitty," a former shoplifter, he deemed it his duty to warn his brother. The Doctor's faith in Julia, however, was not to be shaken. It persisted despite the fact that his rival the Fox, a confederate in the double life of Mrs. Vantine, had made Julia appear a party to theft in order to save himself from the lieutenant's clutches. His love stood a test more terrific. The Fox, frantic by jealousy when Julia rewarded the doctor's faith with her hand, resolved to be avenged on mother and daughter. He turned stool pigeon for the lieutenant, lured the mother into a robbery that she might be caught "with the goods," and he enticed Julia into the house chosen for their robbery in order that she might be discredited in the doctor's eyes. Fortunately, Julia took the doctor into her confidence, and he arrived at the scene of the robbery in time to save her from the Fox. The Fox, goaded into fury by defeat, drew his revolver to shoot the doctor, but his bullet going wild, brought down the mother. When Lieutenant McElroy entered the house to put the Fox under arrest for murder, the doctor easily succeeded in convincing his brother that he had made no greater mistake in his professional career than in presuming that like mother, meant like daughter.