It's official: The ALS Ice Bucket Challenge is back. For those of you who were in a medically-induced coma and/or cut off from all internet access last summer, the titular Challenge involves dousing yourself with freezing water on camera, sharing the video online and challenging your friends to do it, too. If they refuse, they "have" to donate to fund ALS research — though in theory, everyone involved ultimately donates.

As easy as it is to get cynical about any social media meme, the awareness-raising stunt worked: According to, over 17 million people shared their challenge videos on Facebook, and they were watched by 440 million people a total of 10 billion times. As a result, the ALS Association received $115 million in donations over a six-week period in 2014. It was a brilliant success, basically.

The hefty donation pool was due in no small part to a cavalcade of celebrity Ice Bucket Challenge videos that drove clicks and spread the word. It just makes sense — we love to see famous people do silly things, and the fact that it's for a good cause is the cherry on top.

Renee Zellweger and Justin Bieber are two of the first stars to take the challenge this year. Whether the philanthropic spectacle will gain the same level of traction again remains to be seen — but given last year's results, we hope so! Check out the first of 2015's entries below, and if you're inspired to try it yourself, check out the ALS Association's handy how-to.

  • Renee Zellweger

    Renée opens her challenge video standing in a tub in front of an indifferent horse. "After this, I am officially challenging my two English pals, Eddie Redmayne and Colin Firth." She dedicates her impending ice-dump to her friend Nanci, and soon she's screeching in a hail of ice cubes.

    Evidently well aware that California's in the midst of a drought, Renée plans to share her gently-used water with that bored horse.

  • Justin Bieber

    The Bieb steps up for "part two" following his accepted challenge from Scooter Braun last year. Despite the odd camera angle — possibly fish-eye, inexplicably aimed at the sky — Justin clearly gets it done in a tight, Instavid-friendly 15 seconds. Before he takes his bath, he challenges Pastor Judah Smith, Scooter, and...Floyd Mayweather.

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