Isn't it usually the other way round? A pair of 'shark dogs' who seem to round up the animals like they're sheep, turned physical and lunged at a shark under the water in the ocean on the Australian coast.
And the video footage of the attack has gone viral, becoming a top internet hit.
The footage shows two dogs swimming in the ocean near the West Australian town of Broome, about 1,650 km (1,025 miles) north east of Perth.
The dogs appear to be herding several sharks toward shore, when one mutt suddenly ducks under the water and attacks one of the predators.
You can hear Russell Hood-Penn, who taped the incident, shouting: 'The dog is biting the shark. That is unbelievable. I've seen it all now.'
Hood-Penn placed the footage on YouTube, where it has been viewed more than 27 million times.
When the camera pans out, a dead dugong (a large marine mammal similar to a manatee) can be seen beached on the shore and Hood-Penn speculates that is the reason the sharks are circling so close to shore.
At the end of the video the dog emerges from the ocean and shakes the water from its fur.
And we thought it was a dog eat dog world...
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