Three-time Grammy Award-winning pop artist Olivia Rodrigo shocked Brooklyn music lovers on Sunday evening when she performed an impromptu, acoustic version of her new single “Drop Dead” for an intimate open mic night.

But for Brooklyn-based R&B/rock artist Industry Monk, the night was surreal, particularly about 60 seconds after he finished his performance, when, completely by surprise, he realized the artist taking the stage at Pete’s Candy Store in Williamsburg, directly after him, was Rodrigo.

Industry Monk, whose real name is Zach  Kennedy, told amNewYork that he was putting his guitar away after playing one of his songs called “Stayed” off his new album “MONK,” when he heard Rodrigo singing. He said it took him a minute to recognize the voice, but once he heard some lyrics that nodded to The Cure’s “Just Like Heaven,” he started to suspect that the international pop star had actually taken the stage after him.

“I kinda ran back in and popped my head in and did a double take and it was her,” he said.

Apparently, he wasn’t the only one in Pete’s Candy Store, the intimate music venue, who was stunned.

“By the time people kind of figured out what was going on, I feel like there was a respectful silence that fell over the room, and she started shredding and crushing the song,” Kennedy said.

The performance lit the internet on fire, with the lucky few to catch her surprise show posting videos of the “good 4 you” artist performing at the Williamsburg venue on social media.

Kennedy’s post, revealing his surprise and pleasure at “accidentally” opening up for Rodrigo, garnered some attention, with tens of thousands of views, a comment from the official Spotify social media account, and even being shared on NBC’s “Today” show.  

“Me, unaware that I was opening for Olivia Rodrigo at Pete’s Candy Store today,” Industry Monk captioned the video of his set just before Rodrigo hit the stage.

Pete’s Candy Store has a storied reputation as a local “hipster hot spot” where the music is always free and local musicians can cut their teeth in the NYC music scene. But in the more than 25 years Pete’s has been launching local, indie and unsigned artists, more than a handful of famous musicians have graced the stage at the small neighborhood venue — including Norah Jones, Vampire Weekend, Devendra Banhart, Lake Street Dive and Beth Orton.

Kennedy — who has been living in Brooklyn for about a year, making the rounds on open mics across the city — said that seeing such a huge star as Rodrigo dropping in to play a small local venue injected him with a bit of motivation to keep pursuing his own music. 

“After you kind of get over the surreal feeling of it, it’s kind of encouraging when you see someone like that come through,” Kennedy said. “Because that stage is like such an equalizer and you just go and it’s just like: that’s a place where you go to listen to songs.”

He said the experience is making him consider moving from open mics to booking his own shows. 

“ It sort of brings the dream of being an artist, kind of right up close,” he said.

Sunday night’s drop-in performance occurred amid reports that Rodrigo’s first critically acclaimed album, “Sour,” became the first album by a female artist to reach 17 billion total streams on Spotify and the fourth most-streamed album on Spotify of all time.

Rodrigo released the single, “Drop Dead,” earlier this month ahead of her third studio album, “You Seem Pretty Sad for a Girl So in Love,” which will drop on June 12. So far, it’s the only preview fans have of the highly-anticipated upcoming album, save for an exclusive group of invite-only listeners at The Echo in Los Angeles where Rodrigo reportedly performed another unreleased track off the upcoming album with artist Weyes Blood.

In town for her May 2 hosting and musical guest gig on Saturday Night Live, there’s plenty of time for Rodrigo to make more surprise performances around the city and perhaps give NYC fans a taste of some of the yet-to-be-released album.

Meanwhile, Brooklyn-based Industry Monk’s album “MONK” is on Spotify, and while Kennedy told amNewYork he doesn’t have any upcoming shows yet, he has become a bit of a regular at Pete’s Candy Store if folks want to catch him live.