Andover punk-rocker Carissa Johnson survived a room-clearing fire alarm to win Friday’s Rock ‘n’ Roll Rumble final at Once Ballroom, the first female-fronted band to capture the crown since Amanda Palmer did so with the Dresden Dolls in 2003.

Singer/bassist Johnson, guitarist Steph Curran and drummer Nick Hall were busy punching out tuneful punk-pop blasts with the night’s strongest vocals when the PA system cut out and the house lights came on, forcing everybody to evacuate. But when Johnson and her bandmates retook the stage about 20 minutes later, they cranked it up, serving a cover of punk icons the Dead Boys’ “Sonic Reducer” and roaring into a three-way tribal drum bash that spun into their final chords.

Truth was that any of the three competing acts had a great shot to win, as the Rupert Selection and Hey Zeus took their performances up a notch from earlier rounds. The Rupert Selection sparked the loudest crowd interaction, with fans shouting “Hey!” to fill pauses in the Manchester-by-the-Sea trio’s deft, dynamic mash of Nirvana-esque blasts and math-prog rhythm shifts, nimbly juggled by drummer Zak Brown (above). And wild card Hey Zeus flashed the night’s main showmanship with its greasy hard-rock shtick, spiced by the burly guitar licks of Pete Knipfing (below) and the frisky leg kicks of vocalist Nathan Bice (bassist in 2014 winners the Goddamn Draculas), who howled and stomped before an illuminating cross and banged a gong.

As usual, however, the winners were all 24 bands (this year heavy on guitar rock) who took the stage over nine nights of competition, curated and coordinated by WZLX “Boston Emissions” DJ Anngelle Wood and her bustling crew.