As the ALS Ice Bucket Challenge charity drive starts to wind down, there are only a few celebrities left who haven't yet gotten in on the action. A lot of those are ones who are very busy on the very top secret 'Star Wars: Episode 7' set. But, as the challenges continue to pour in, the 'Episode 7' cast has started to do their part, by dumping freezing buckets of ice water on their head.

Above we have star Mark Hamill, looking very much the part of the rumored "missing-in-action" Luke Skywalker from 'Star Wars: Episode 7'. He was challenged by young Daisy Ridley, one of the 'Star Wars' newcomers. (What's interesting about her video is that this is the first time many of us have gotten to see her (and hear her) on camera. Also joining in was Oscar Isaac, who said that we shouldn't hold our breath waiting for either Harrison Ford or Adam Driver.

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But, then, wouldn't you know it? From his home in Wyoming, Harrison Ford uploaded his own ice bucket video, as he's rehabbing from his broken leg:

Even Han Solo's best buddy, Chewbacca himself, Peter Mayhew, got in on the action (while wearing a t-shirt that says "Once you go Wookiee, you never go back"):

Last week, we also had a video from director J.J. Abrams --

-- who challenged the entire 501st Legion, the 'Star Wars' fan organization with over 6,500 active members. They responded in kind with these videos:

As the rest of the 'Star Wars: Episode 7' actors fulfill their challenge from Mark Hamill (who called out the entire cast), we'll continue to update this article with all the latest videos!

'Star Wars: Episode 7' opens in theaters on December 18, 2015.

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