Honestly, after watching this video, I'm not sure there's much more to say.
But there is so much more to say. This is arguably the biggest K-Pop hit of all time. It was released in 2012, and was on the US World Digital Singles year-end charts - so, charts for the whole year - in 2012, 2013, and 2014. No song has charted on that chart (which is a weekly) longer than this one.
The song is a pretty standard dance-club banger, with a Sly and the Family Stone tribute mixed in for good measure. Or did you think the boom shakalaka was just there because it sounded good? The beats draw you in - it's a catchy song lyrically as well, especially if you know Korean.
But this video. My God. It's a bit much. And amazing. And a bit much.