The announcement dropped on a pulverizingly humid Thursday afternoon in New York City: just a few hours later, an Olivia Rodrigo surprise gig would take place at Brooklyn’s intimate, 1,100-capacity venue Warsaw. The expected mad dash for tickets — only available at the venue’s box office — ensued, with fans lining up in heat that was technically 91 degrees but with a “real feel” of 105. But of course, the venue was packed long before the 8 p.m. showtime, even though it was just as hot inside.  

Rodrigo, clad in a red flowered schoolgirl dress and black go-go boots, dove in at the deep end, starting the set ambitiously with the album’s first single, “Drop Dead” — a challenging song to sing, with its upper-register chorus that offers few opportunities to take a breath — but she pulled it off with ease. “We’re going to be playing a lot of songs from my new album for this first time,” she said, and promptly obliged with three more tracks from “You Seem Pretty Sad for a Girl So in Love,” concluding with the Wet Leg-esque “My Way.”

Her five-piece band was razor-sharp — they’ve played a number of concerts this year, from the Primavera Festival in Spain and “Saturday Night Live” to a surprise cameo with the Smashing Pumpkins at Lollapalooza last weekend — but apart from an “Austin City Limits” taping last weekend, this was indeed the first time most of the eight new songs have been performed for a concert audience.

After the opening blast, Rodrigo then sat at the keyboard for a brace of ballads from her previous albums, including “Drivers License,” before rolling out four more new songs — including the fan favorites “Maggots for Brains” and “The Cure,” the latter of which she said is “probably” her favorite song from the album, as well as an emotional debut performance of “Less Than” — before finishing off the set with “Good 4 U” and “Déjà Vu.”

Throughout the set, she was her usual effervescent self, bouncing, spinning, holding out her arms, pumping her fists and leading the audience in several singalongs — and not a word about her latest altercation with the president. The “Pretty Sad” songs were note-perfect, but new material always takes a few gigs to break in and it’s likely they’ll be looser as time goes on. Likewise, a few older songs will probably be added to the setlist before they begin touring in earnest, beginning with Rodrigo’s own Daisy Chain Fields festival in Southern California at the end of this month, and the months-long “Unraveled” tour, which launches on Sept. 25.