He drives on a bit until curiosity finally gets the better of him and he returns to the farmhouse. He rings the bell and the owner appears and tells him the dog is in the backyard. The guy goes into the backyard and sees a nice looking Labrador retriever sitting there.
"Do you talk?” he asks.
“Yep,” the Lab replies.
After the guy recovers from the shock of hearing a dog talk, he says “So, what’s your story?”
The Lab looks up and says, 'Well, I discovered that I could talk when I was just a pup. I thought I could put my talent to good use by working for the government, so I made contact with military intelligence. In no time at all they had me jetting from country to country working for MI6, sitting in rooms with spies and world leaders, because no one figured a dog would be eavesdropping. Every time my guy left to use the facilities, I'd be picking up the juicy stuff they didn't want him to hear. I was one of their most valuable spies for eight years running but the jetting around really tired me out, and I knew I wasn't getting any younger, so I decided to settle down. I signed up for a job at Glasgow Airport to do some undercover work with the Customs officers, standing 20-30 feet away from the desk and picking up all sorts of revealing information. I uncovered some incredible dealings and was awarded a batch of medals. After a while, even that became a bit tiring so I chucked it in, got married, had a load of puppies, and now I'm just retired.”
The guy is amazed. He goes back in and asks the owner what he wants for the dog.
“Ten pounds,” the guy says.
“A tenner? This dog is amazing! Why on earth are you selling him so cheaply?”
“Because he's a fucking liar. He never did any of that shit.”
Top that Inspector Rex