At the Drive-In, Brixton Academy, London

All friends again: Cedric Bixler-Zavala and co meet up for a long-anticipated reunion at the Academy in Brixton (Simon Parry)

"We consider this the last show of the Relationship of Command tour," keyboardist/guitarist Jim Ward lets us know at the end. "It’s taken us 12 years to finish." Then he adds, of his four band-mates: "I love these dudes more than life itself."

That didn’t seem to be the case when At the Drive-In pulled out of the final dates of their February 2001 tour then split at the height of their success, shattered by the usual brutal schedules, drug abuse, creative exhaustion and bickering.

The Texans’ reputation as trailblazers of a post-hardcore, more melodic punk sound endured, even as singer Cedric Bixler-Zavala and guitarist Omar Rodriguez-Lopez formed the progressive rock band The Mars Volta, eventually joined by bassist Paul Hinojos.

At the Drive-In’s reunion this year was sudden and, with no new recording intended, may be brief. But looking at Ward especially, who self-consciously watches the packed, heaving crowd, and finally gives a shy grin, these shows seem more about restoring friendships and finishing well than cashing in or coming back.

It is also punishingly loud. Standing near one of the six-speaker stacks flanking the stage, I fear for my hearing. But the band seem better and subtler than when I saw them in 2000, just before they split. Bixler-Zavalas picks his way rhythmically through “Metronome Arthritis”’s syllables, and elsewhere almost croons.

His restless, mildly sarcastic dissatisfaction, which helped fuel then split At the Drive-In, comes through in these vocal shifts, when he’s not bulleting out the words and hurling his mic-stand. He frequently sips a mug, maybe just of tea, and watches the band during the contemplative instrumental passages which thankfully break up their crowd-inciting punk force, as with “Napoleon Solo”’s sections of drifting beauty.

Tony Hajjar’s bass-drum cracks that song forward, but he also shapes the music like a jazz drummer. There are pizzicato guitar plucks and a slow sense of swing, the “post” bit of post-hardcore.

They finish with their biggest hit, “One Armed Scissor”, causing a final fling of joyful moshing in the crowd. “I smell like a Burger King Whopper,” Bixler-Zavala confides, and Brixton Academy has a locker-room odour as the sweating fans leave. Hajjar holds up his toddler son Milo just before they do, so he’ll know what his dad once did. At the Drive-In can finally leave smiling, only 12 years late.