A Polar Bear Roaming London? No, It's Just A New Video From Greenpeace

If you thought the streets of London are dangerous now, imagine what they would be like if polar bears were roaming around.

Gangs of feral youths looking to steal trainers and TVs would seem like a picnic compared to the threat of the world's biggest land carnivore rustling around your rubbish bins.

It is a nightmare vision brought to life in a new campaign from Greenpeace, which also stars Jude Law and the bleak music of Radiohead.

But if you thought the video was designed to make you scared of leaving your house through fear of imminent bear invasion, guess again.

The ad is in fact to promote Greenpeace's Save the Arctic campaign, which the environmentalist group says "aims to protect the Arctic from oil drilling, industrial fishing and militarization".

The ad shows a hungry polar bear trying desperately to survive in London. It finally gives up and lays down to die in a park.

As Law's voiceover says: "Our leaders won’t listen to her, but they’ll listen to you. What do you have to say to those who want to destroy the Arctic?"

It is a very sad clip, which has attracted a lot of attention on the web so far. Since being launched on July 2, it has been shared almost 30,000 times across Facebook, Twitter and the blogosphere. The most poignant moment is when the bear reaches down to sniff at a car's exhaust pipe.

Law wrote: "As the Arctic sea ice melts, polar bears are being forced to go far beyond their normal habitat to find food and look after their young.

"This film is a powerful expression of how our fates are intertwined, because climate change is affecting all of us no matter where we live.

"Right now a handful of oil companies are trying to carve up the Arctic for the sake of their next quarterly results but a global movement is growing to stop them.

"I stand with hundreds of thousands of others who think the area should be made into a sanctuary, protected from corporate greed for good."