The Regrettes. Photos: Joaquin Cabello

SAN FRANCISCO — Up until they brought out their secret weapon, SoCal pop-punk band The Regrettes was in the middle of another strong Bay Area showing at The Chapel. Frontwoman Lydia Night, all of 17 years old, was snarling and delivering the lines to cuts like “Hey Now” and “Whatta Bitch” in rapid fire. Guitarist Genessa Gariano didn’t miss a lick of her riffs, and bassist Sage Chavis was laying down the rhythm to anthem after anthem, alongside the band’s new drummer, Drew Thomsen.

Then the Regrettes broke out a nearly six-minute cover of Rage Against the Machine’s “Killing in the Name” for the first of two encores. Fans, who had squeezed to fill every possible space near the stage, went nuts as Night screamed the lines into their faces without losing the key, and the band performed the song faithfully.

Up to this point the band, Night and her bandmates have written songs about their lives, and the lives of their friends. They were about pimples, bullies and self-acceptance. “Killing in the Name Of,” though a cover, felt like the Regrettes were stepping into new territory, and they did it ferociously.

The most noticeable initial difference at Wednesday’s show was the absence of drummer Maxx Morando, who left the band in May. Thomsen, with his curly hair, looked not too unlike his predecessor. His bandmates were still feeling him out and didn’t involve him in the stage interplay as much, but musically, he was more than capable and had his parts memorized.

“We have wanted to headline here for so long,” Night said, beaming, following set opener “I Don’t Like You,” off the band’s 2017 debut LP, Feel Your Feelings Fool! “Hey Now,” another older track, came next, but a good chunk of the band’s 60-minute set consisted of newer songs from 2018 EP Attention Seeker, and even newer material.

New tunes like “Dress Up” and “California Friends” fit right into the flow of the show. Throughout, mosh pits formed morphed from one side of the floor to the other. Night had the crowd perform the “wall of death,” where fans were split down the middle of the floor and run into each other, and Night even went crowdsurfing during the second encore, which included “Juicebox Baby” and The Sweet’s “Ballroom Blitz.”

Openers Kid Bloom, a Los Angeles quintet, deftly blended psych-rock with funk, power pop and disco. Frontman Lennon Kloser, guitarist Zach Tabori, drummer Clayton Sewelson, keyboardist Bobby Victor and bassist Blake Morell didn’t even flinch at the stylistic changes.

Victor starred on the band’s funkier songs, like “She Only Stays on the Weekend,” while Tabori held center court on the power pop numbers, like new single “Parents House.” Kloser joined the soloing act by playing riffs from AC/DC’s “Thunderstruck” and Guns N Roses’ “Sweet Child of Mine.”

The band changed styles so often, sometimes mid-song, that its influences were difficult to peg; somewhere between Hall and Oates, Tame Impala and David Bowie.

Follow editor Roman Gokhman at Twitter.com/RomiTheWriter. Follow photographer Joaquin Cabello at Instagram.com/joaquinxcabello.