Remember back in October when a load of YouTubers hosted a 12 hour live-stream and raised a shedload of money for Stand Up To Cancer? Well, it was such a roaring success that it's happening all over again.
Basically, a load of the best vloggers around will participate in a bunch of challenges over a 1000 hour window; Zoella, Alfie Deyes, Dan and Phil, Caspar Lee, Joe Sugg, Marcus Butler, Jim Chapman and quite literally loads more will be getting involved.
Check out their official portraits, snapped by Linda Blacker, below:
Dan and Phil
Joe Sugg and Caspar Lee
They're kicking the whole thing off on September 3rd by trying to keep silent for three hours.
Casper exclusively told us: "Joe can make me laugh just by looking at me. We know each other so well that all it takes is one raised eyebrow or silly face and we both end up in stitches - I'm genuinely going to find this a big challenge!"
Niki and Sammy
The Mandeville Sisters
Each of the YouTubers will announce their challenges over the coming weeks leading up to to the live-streamed YouTube event, which will kick off on Saturday 15th October. EXCITING, and all for a good cause too.
Round of applause, everyone.
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