Lorde scripts a party, and then brings it

Lorde performed in concert at TD Garden on Tuesday night. Matthew J. Lee/Globe staff

Writers are naturally observers — hiding in the shadows, scanning passersby for quirks in their expressions and the scenery for any clues as to a place’s overall mood. In that sense, it was quite savvy for the New Zealand-born singer-songwriter Lorde to turn her second album, “Melodrama,” into a concept album about a party; she’s a natural observer not just of how others interact and come together in joy and in sorrow, but of how she fits into that churn, and how she feels about those connections and ruptures. Parties are an ideal setting for exploring and exploding that tension — the promise of fun is an imperative, but the possibility of something much worse always looms.

Lorde (born Ella Yelich-O’Connor) came to prominence with the 2013 single “Royals,” a chronicle of the outsiderdom experienced by broke teenagers looking for a good time that was propelled by a skeletal, yet insistent beat. “Melodrama,” as befits its name, ups the musical ante; it brings in rubbery New Wave synths and pianos that echo classic Chicago house records, giving extra gravitas to the singer’s signature touches — low-slung yet acerbic vocals, spectral vocal harmonies, and lyrics that seem to tumble out of her mouth stream-of-consciousness style. Tuesday night’s fast-paced, yet emotionally resonant show at TD Garden was a superlative showcase for “Melodrama,” which can sound a bit overdone in its recorded form. Lorde, her backing band, and her troupe of dancers gave its songs a workout, showing off their sometimes left-field structures and telescopic lyrics; the shared-secret verses and self-deprecating witticisms of “The Louvre” opened into a starlit, anthemic chorus, while the existentially tormented “Perfect Places” turned into a cathartic singalong, its unprintable refrain sounding jubilant when multiplexed.

The stage setup was sparse, but it reflected the writer’s life in a way — the dancers would often perform while encased in a glass box, their bodies moving and joining while separated from Lorde. She did enter the box occasionally, including during a midshow costume change; she’d also break out into brief, ebullient dancing, then stop short in a way that felt like she’d suddenly felt seen. (Obviously, she was seen, but the way she lost herself in the music was relatable.) The stripped-down emotional heart of the show began with a monologue about her feeling like an outsider, which turned into a metaphorical group hug for all the outsiders, followed by three ballads where she was accompanied only by piano. Among them: “Writer in the Dark,” a somewhat spiteful, yet deeply felt kiss-off to a lost love that showed off her voice’s searing upper range and included a lightly taunting refrain: “Bet you rue the day you kissed a writer in the dark.” But that release of tension only amped up the show’s back half, sealing the deal on Lorde’s show being one of those parties that, thankfully, made good on its promise of unbridled fun.

Lorde

With Mitski, Run the Jewels

At TD Garden, Tuesday