Unlike most of the celebrity ALS Ice Bucket Challenge videos we've seen, Matt Damon's version tells a story, specifically about why he decided to pour toilet water (you read that right) all over himself. As Matt explains, he has a very good reason for doing something that sounds so ridiculous. Don't let that keep you from watching the video, though — you wouldn't want to miss out on Matt's infectious smile, which makes more than a couple of appearances. Plus, he's looking really buff these days!