A man sees a sign in front of a house: "Talking Dog for Sale". He rings the bell and the owner tells him the dog is in the backyard. So the man goes to the backyard and sees a black mutt sitting there. âDo you talk?" he asks. âSure do", the dog replies. "So, what's your story?" The dog smiles and says, "Well, I discovered my gift of talking pretty young and I wanted to help the government, so I told MI5 about my gift, and in no time they had me jetting from country to country, sitting in rooms with spies and world leaders, because no one figured a dog would be eavesdropping. I was one of their most valuable spies for over eight years. But the jetting around really tired me out, and I knew I wasn't getting any younger and I wanted to settle down. So I signed up for a job at the airport to do some undercover security work, mostly wandering near suspicious characters and listening in. I uncovered some incredible dealings there and was awarded a batch of medals. Then had a wife, a mess of puppies, and now I'm just retired." The man is amazed. He goes back and asks the owner how much he wants for the dog. The owner says, "Ten quid." The man says, "This dog is amazing. Why on earth are you selling him so cheap?" . . . . . . . . . . . . . . . âBecause he's a liar. He's never done any of that stuff."