Actor and comedian Brian Jordan Alvarez is a prolific poster online. Now, one of his latest videos has taken on a new life.

Who is he? T.J. Mack is a wide-eyed popstar who loves to sing, shop and talk about his wife.

• Mack is one of the many characters created by Alvarez, a Colombian American actor, comedian and filmmaker who has starred in TV shows and movies like the reboot of Will & Grace, and M3GAN.

What's the big deal? Simply put, sitting is the opposite of standing. And if that doesn't make sense, it soon will.

• Earlier this month, Alvarez posted a video of the Mack character on X, with his signature bug-eyed filter, singing a catchy little tune about how he enjoys sitting down. You can watch for yourself below, but be warned, it will likely get stuck in your head.
  

• Since then, like every other inexplicably popular earworm, the song has taken off, garnering millions of views on X, and raking in others on Instagram and TikTok. Sittingmania has resulted in a bevy of remixes and covers, ranging from techno to screamo to indie folk.

• The unofficial fan favorite is a remix by New Zealand musician Josh Mac, which has gained more than 100,000 plays on Spotify since being released earlier this week, and even got some airtime on an Australian radio station.

What's he saying? Alvarez chatted with All Things Considered host Ari Shapiro on the life this video has taken on.

You've made more than 100 videos as T.J. Mack. So when the sitting song came to you, did you think, "Oh, this is my 'Unchained Melody,' this is my 'Like a Prayer'?"

I did feel like it was special, you know? And the funny thing is, usually my videos are very off the cuff. I do one take and I post them. And this particular song I did a take, and for some reason the sound didn't record. So I did it again. And the second time I did it, it was a bit tighter and cleaner.

What has it been like to see all of these people reacting to your ridiculous song?

It's been incredible. And the funny thing is, I do all these characters. And so now I have this song and the song has a structure. It's got bones, right? And then you're sort of seeing the song do characters. So the song is becoming all these different songs that it could be in this sort of multiverse of sitting madness.

Brian, what advice can you give us all for getting the song out of our heads?

I think, keep listening. Keep letting it go deeper and deeper. And it's going to work itself out. If in the process of getting the song out of your head, you need to release a fully produced cover of the song and post it online, I encourage you to do so. I think that's the best remedy.

You know, one of my colleagues said, "He must be really annoyed that this is what has made him this famous." But I get the sense that, no, you're leaning into it. You're just devouring it all with gusto.

I am overjoyed. You know, I couldn't be happier that this is having this moment. And I've done little songs like this my whole life. And I have in many ways dreamed of different versions of this moment, so I'm grateful.

So, what now?

• Analysts predict that chair stocks will skyrocket in correlation with the popularity of Mack's song.

• That is not true. I just made that up.

Learn more:

• Taylor Swift enters her football era and breaks the internet

• A Beyoncé fan couldn't fly to a show due to his wheelchair size, so he told TikTok

• TikTok has changed music — and the industry is hustling to catch up

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