Standing on a rooftop balcony, Olivia Wilde revealed to the camera that she 'couldn't find any water'.
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So, instead, the Tron: Legacy actress decided to take the ALS Ice Bucket Challenge to a whole new level.
She said simply: "I hope it's OK but I couldn't find any water, so I'm going to use breast milk.
"It took me all night to make this."
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The 30-year-old then upended a bucket over her head, soaking herself in a seemingly endless supply of the thick, milky substance.
Watch the clip for yourself below:
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Not all was, however, as it seemed - as we're sure many of you will have guessed by the unrealistic amount of milk she poured over herself.
Olivia took to Twitter to rectify the situation.
She tweeted: “Oh wait some of you thought that was really breast milk? Oh dear.
"Uh thank you? But my boobs aren't that generous. Haha.”
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Could this be the weirdest ALS Ice Bucket Challenge yet?