You might think a rescue worker who claimed their Chihuahua could herd sheep was pulling the wool over your eyes.
But Battersea Dogs and Cats Home has revealed 2.5lb Nancy's impressive talents with a video clip on the internet.
She makes quick work of showing five sheep who is boss, despite the animals being more than six times taller than her.
Owner Ali Taylor, who is also head of canine welfare training at Battersea, said the dog was always interested in watching border collies herd sheep.
"One day I decided to give her a whirl in the ring and she picked it up straight away," she said. "I started in a very controlled environment but it quickly became evident that Nancy has natural ability and loves herding sheep."
The Chihuahua was taken to the rescue centre at just three weeks old with severe sarcoptic mange and had to be hand-reared.
Ms Taylor added: "People sometimes underestimate rescue dogs but they really are fantastic and go on to do amazing things."
The charity stresses that no one should try sheep herding without expert supervision.
The video of Nancy in action is at: www.youtube.com/watch?v=G40vwF4YNC4