Warning - this video is not safe for life. Don't watch if you're squeamish. Don't watch it at all, really, it can never be unseen.

This video of leg cramp might be the worst thing we've seen on the internet since Two Girls One Cup.

It was put online by Australian Redditor dogzfan who claimed it was a Snapchat of his friend's calf - but like Digg, we're hoping it's just "viral marketing for a new Alien movie".

Watch it below, but you can't say we didn't warn you.

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