This Border Collie dog stares up at the vet's wall with suspicious eyes. What exactly is he staring at with so much intensity?

His owner Kelsie gives the answer in a curious TikTok video that has attracted millions of viewers.

Kelsie's clip begins with the dog sitting rigidly as he looks upwards. The comical video is accompanied by extremely dramatic music: Tchaikovsky's Swan Lake.

Finally comes the denouement – the camera pans upwards to a door frame with a cat decal stuck to it.

Dogs Dog owner is shocked when she sees what her mother-in-law has done to her pup!

Dogs Deaf-blind dog wins heart of kitten in heart-melting video

The Border Collie obviously doesn't notice the illusion, even though he is looking so closely.

On the contrary! When the camera pans back to him, he has bent his right front paw and moved a little closer to his "target."

So why is he doing all this? Well, there are two good explanations for this intense behavior.

Firstly, Border Collies are considered to be highly intelligent dogs, specializing primarily in herding sheep.

When the breed wants to get other animals under control, it is known for its fixed and stern gaze.

The deep look into the eyes, in particular, gives the pooch an impressive sense of authority.

Dogs Polite puppy stuns foster mom with his adorably good manners!

Dogs Puppy loves to imitate his big brother in so many sweet ways!

The viral hit is therefore a prime example of this Border Collie behavior.

There is also a private background context.

In a second video, owner Kelsie reveals that her dog also has to deal with cats at home on a daily basis.

In the clip, the Border Collie fixates on one of Kelsie's kitties with similar intensity!