Best of 2021 (Behind the Scenes): How In the Heights lyrics became summer's viral TikTok trend

"You been shaking your ass for like halfa of da heights…"

It was the drunk chastisement heard round the internet when a simple exchange between Usnavi (Anthony Ramos) and Vanessa (Melissa Barrera) from In the Heights became the TikTok obsession of the summer. So much so that the film's stars, including Ramos and Barrera, and creator Lin-Manuel Miranda uploaded their own takes on it.

The brief musical exchange comes from "Blackout," a climactic moment in the film when a New York City blackout sends Washington Heights and the protagonists into chaos, as they try to find their way home and protect their neighborhood.

Baylor University freshman Katie Bradshaw was the one to kickstart the trend, posting the audio from the song and her own performance on TikTok after seeing it. "When I went to see the movie in the theater, I quickly became obsessed with that part of the song," she tells EW. "I got my friend hooked on it, and we just kept singing that one section over and over. I noticed that it wasn't on TikTok and I was like, 'Why not?! This is amazing. Everybody needs to be listening to this song — and especially this part' — so I just uploaded it myself."

Funnily enough, these lyrics weren't even a part of the original Tony-winning score, but penned for the film. They were added at the behest of director Jon M. Chu. "Usnavi is an almost too likable person in our movie, and this is the one time where he becomes an a--hole, and she gets to tell him off," Chu says of the moment.

Chu knew he needed Usnavi and Vanessa to have a fight during "Blackout" to propel the film to its conclusion. Early in pre-production, he went to Miranda's house along with orchestrator Alex Lacamoire and screenplay/book writer Quiara Alegría Hudes. "'Blackout' in the show is this big event," the director explains. "We had to reconstruct it in our movie and rather than send notes back and forth, we all got in a room at Lin's house one night."

Never one to not be prepared, Chu came with a version of what he wanted mapped out his head, explaining what he wanted to see and what each group of characters needed to do in the number. "But then they take it and they run with it," he marvels. "I watched them create it in like 15-20 minutes with Alex on piano, Lin standing there, and Quiara right behind them."

Chu wanted to chime in, but Lacamoire, Miranda, and Hudes' brains all work so quickly he could barely keep up. That night they built the section for what would become Vanessa and Usnavi's argument, but it wasn't until a few days later that he got the actual lyrics.

"Lin wrote those lyrics and recorded himself on a voice memo and sent it to me," he says. "He did both voices. So, you could say, I had this meme before anyone knew it was a meme."

When Bradshaw uploaded her video and the sound to TikTok, she didn't expect it to become an explosive trend. She just liked the music. "I love the tension between the actors. It was just a whirlwind of emotions they were portraying perfectly," she says. "I did find it attractive — the way he said it. As a female, I think some parts of it are problematic, but my original draw to that section was, 'Wow, I like the way he's saying this.'"

All that sexual tension and frustration that captured hearts and minds partly came out of shooting conditions on the day. Chu says it was the last shot of the night, and they were racing against the rising sun to get it in the can. Indeed, he says if you look closely, you can even tell that it's lighter in the sky (and they digitally darkened it a bit in post-production).

They filmed under an overpass near Washington Heights (though they recorded all the singing live, they ended up using a post-record due to the sounds of early morning traffic). "It was cold out, Melissa is in a small green dress, and it's a real alleyway so the concrete isn't even that safe," Chu remembers. "We made it more safe, but we had to fill in potholes and cracks with sand or wood and gravel because she's in her heels."

"They have to walk with a [one-shot]," he continues. "We're not cutting around them. They have to deliver it in real time. And the camera has to be perfect going around them. Our extras, who are walking as if they're club-goers, have to walk past. We have certain flashlights and flashes that are going off. It was emotional."

But all of that is what he thinks made the moment so potent and thereby ripe for an internet trend. "That night was very hard for us," he admits. "It was a frustrating night. They were both in the mode of being frustrated and getting all that out. You feel like you're witness to a real fight between two people. At the end, she look him up and down, and it was five in the morning, the sun's about to rise, and that look of disgust was – all the dudes felt it. Like, you do not want to get that look."

Still, no one expected this to become the viral hit of the summer. In fact, Chu thought another lyric change was far more likely to resonate — one with a Star Wars reference. "There was a line in '96,000' that I wanted Lin to replace about, 'Got more Hos than a phone book in Tokyo' because I thought that was kind of offensive,'" he says. "So he wrote a new one that I thought was dope. He wrote, 'I got more flows than Obi Wan Kenobi, yo.'"

They even went so far as to animate that lyric with a lightsaber and use the sound effect of the iconic sci-fi weapon (a step that required rights approval from Lucasfilm). "But I was wrong, nobody paid attention to that one," laughs Chu. "No one said, 'It's different.'"

But 'Blackout' began to take off after Bradshaw uploaded the audio and posted her version. "Every week I would check on it, and I was like, 'Oh my gosh, there's like 1,000 people that have used my sound, This is crazy,'" she remembers. "And then like the next week, it'd be like 100,000. And then all these Tik-Tokkers that I follow started using the sound."

Chu didn't realize at first quite how big it had become. He had his social media feeds set to search the hashtag for In the Heights, so he assumed the glut of videos was just a result of his algorithm. It wasn't until the cast and crew started sharing the videos on their group text message that he knew it was rapidly turning into a viral trend.

It became so popular TikTok even created a special filter for it, giving a red and blue light to indicate whether Usnavi or Vanessa was singing. Chu thinks it took off because it allowed so much creativity with the two roles, the gender-swapping, and the special filters.

Then, the cast got in on the fun too. Ramos and Barrera gender-swapped it playing each other's roles (Chu's personal favorite); Leslie Grace (Nina) played both parts, drawing on and wiping off a mustache as she switched between them; and Miranda "closed the loop" with Broadway's original Vanessa, Karen Olivo, again gender-swapping the roles.

"My heart started to race when I saw Anthony and Melissa do it," Bradshaw gushes. "I knew it was a trend. I knew people were doing it. But when they did it, I was absolutely starstruck. And then, Lin did it, and I was just like, 'Wow.' I had never intended, by me posting this one little part me and my friend were obsessed with, for it to reach the stars of the film."

Chu tells EW that he even recorded his own version that he doesn't plan to share publicly. It's him performing the segment with his then 3-year-old daughter. Though this has inadvertently resulted in him trying to coax his toddler into not loudly proclaiming, "You been shaking your ass for like half of the heights."

"I'm trying to get my daughter not to say it," he laughs. "She knows all the words to all the songs. I'm like, 'Ok, let's not learn those lyrics.' How about, 'I got more flows than Obi Wan Kenobi?'"

May the force be with you on that one, Jon.

Related content:

• Read more from EW's Best of 2021 coverage
• The 10 best film scenes of 2021
• Go inside the making of In the Heights with this exclusive excerpt