guy is driving around Tennessee and he 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. The guy goes into the backyard and sees a
Labrador retriever sitting there.
"You talk?" he asks.
"Yep," the Lab replies.
"So, what's your story?"
The Lab looks up and says, "Well, I discovered that I could talk when
I was pretty young. I wanted to help the government, so I told the CIA
about my gift, and in no time at all 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 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 the airport to do some undercover security wandering near
suspicious characters and listening in. I uncovered some incredible dealings
and was awarded a batch of medals."
"I got married, had a mess 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 dollars," the guy says.
"Ten dollars? This dog is amazing. Why on earth are you selling him so
cheap?"

"Because that mutt is a F'in bald-faced liar. He never did ANY of that sh!t!!!!!!"