He had barely entered the hall than a prominent banker, known for the keen interest he took in the development of the dog, and who was one of the officers of the society under whose auspices the dog show was held, greeted him with the remark: “Of all men, Mr. Carter, you are the man I most wish to see. Some miscreant is poisoning our dogs here. The fourth animal is just now dying from a dose—all valuable animals.” “Have you suspicions?” asked Nick, scenting mystery at once, and nothing loath to tackle another puzzle now that he had placed the Brown Robin behind prison bars. “Not the slightest suspicions,” replied the banker, “although the owner is making wild charges and threats, but, then, that is from her grief.” “Her?” asked Nick, in surprise. “Yes; Mrs. Constant—poor Al Constant’s widow.” “Were all the dogs poisoned owned by her?” “All of them.” “Do you think it possible that rivalry or jealousy could be at the bottom of it?” “In the contest here for prizes, do you mean?” “Yes.” “I cannot believe it.” Nick asked no more questions, and looked over the room. “Come with me and look at the dog,” said the banker. Nick nodded, and the banker led the detective to a rear room, where he saw a noble setter dog writhing in agony on a blanket on the floor. A well-known veterinary surgeon was laboring over the dog, and a beautiful woman of thirty, regardless of her costly raiment, was kneeling at the dog’s head, soothing and petting him, the tears streaming from her eyes, while she murmured: “My old Don! My poor old Don!” The dog’s eyes were glazed, and Nick saw at a glance as he came up that the dog was dying. But from time to time, the poor beast would turn a look of deep affection on the beautiful woman and lick the hand that soothed and petted him. “Mrs. Constant.” said the banker, “here is Mr. Carter, the celebrated detective. I have hopes that I can persuade him to look into this case.” “It is too late to save my poor old Don,” said Mrs. Constant, looking up. “As for the miscreant, I know him. He is——” “One moment,” hastily interrupted the banker. “What you have to say as to charges and suspicions say to Mr. Carter alone. He is to be trusted, and his advice will be well worth following.” Mrs. Constant looked up at Nick, smiling through her tears, and said: “Very well. When can I talk to you, Mr. Carter?” Handing her his card, Nick said: “Come to my house when you can.” “I will do so,” said Mrs. Constant, “as soon as I have seen poor old Don cared for and my other dogs out of harm’s way.” Now the dog had another spasm, and it proved to be his last. He stiffened out and died. Nick turned away and went into the show room to inquire as to the manner in which the dogs on exhibition were guarded and cared for, and in doing so passed half an hour inspecting the dogs. At the end of that time, as he approached the center division, he saw Mrs. Constant standing beside a dog with her hand upon its head.