So, what is the ice bucket challenge?
You might have noticed a lot of celebrities dousing themselves with buckets of ice water on camera recently.
If you've thought ‘what’s that about?’, well here’s your answer.
Called the ice bucket challenge, it was created by the ALS Association, who are working to fight Amyotrophic lateral Sclerosis (ALS), also known as Lou Gehrig’s Disease or Motor Neurone Disease in the UK.
The challenge is this: film yourself getting doused with a bucket of ice water, post the video to social media and then nominate your friends to do the same.
If you’d rather not have freezing water dumped on your head, you are asked to donate to an ALS charity of your choice.
So far, the challenge has been undertaken by the likes of Oprah Winfrey, Robert Downey Jr, Bill Gates, Gwen Stefani, Michael Zuckerberg, Taylor Swift and Cristiano Ronaldo.
Most recently the hosts of Susanna Reid and Ben Shepherd of Good Morning Britain got in on the act.