One man unwittingly took part in a You've Been Framed moment when he was chased out of the water by a shark - not realising that it was only someone carrying a fake fin.
The mean trick is thought to have been filmed at Woffard Heights in California, according to the Daily Mail.
The footage shows three men swimming in a lake when one of them shouts 'shark'. One terrified swimmer then looks behind him to see the 'shark fin' heading towards him, and makes a dash for land as quick as his arms and legs will carry him.
His friends can be heard shouting "keep going" in the background, and the man makes it to shore to the sound of hoots of laughter.
The video doesn't shoot for long enough for the viewers to find out whether the victim of the prank saw the funny side or not.
Many Live Leak users came to the defence of the man who may have been left with a slightly bruised ego, with one writing: "Oh how I would have loved to have seen a real shark take a bite from the guy with the fake fin..."
And another wrote: "Don't blame him one bit.... When I go to the beach and something touches my leg I'M GONE... Just like jesus I walk (run) on water."
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