The heat within the Underworld is palpable, the air clammy and the crowd spattered with spilt beer as, at the front of the stage, a broad shouldered man with a shaved head spins his arms in a windmill gesture and kicks out wildly, much to the consternation of a worried looking security guard in the corner.

He doubles over, elbows bent, the ape movements of a gorilla wildly re-enacted amidst the spreading dead space around him, until at last he crashes into friends and is ultimately rebuffed.

We all know these frantic movements, we all know their context and meanings and had we not been aware before 1994, then we certainly have the promotional video for Sick of it All’s Step Down to thank since then.

When I talk about hardcore, I am invariably talking about bands such as Sick of it All.

Hailing from Queens, New York, Sick of it All are one of the most influential bands to come out of the New York Hardcore Scene, a blistering noise that gave voice to all the anger and fury of a genre that had quietly become tainted by its brush with the mainstream of the middle classes.

Honourable mention should be made at this point of London based group, Knuckledust who set the stage for the night’s headliners as one of two support bands with a glorious message of solidarity and strength. With guitarist Wema’s face obscured by the rim of his baseball cap and his voice loud, with lead singer Pelbu’s heartening recommendation of respect for the scene and for the need to show respect for others, Knuckledust are quite clearly one of the most underrated bands I have seen play live this year.

When I talk about hardcore, I am talking about the true voice of punk rock.

Playful and irreverent Lou Keller stands before the audience as kids half his age launch from the stage and into the pit and shouts out, “Let’s celebrate that we don’t give a fuck with the middle finger high in the air,” and the message rings out loud in the air around us.

A drunken fan stumbles between the stage and the stairs leading up to the bar, concerned looks on the faces of younger fans as several men his own age lift him up and forcibly carry him out of the pit, making sure he is as unharmed as can be.

Sweat stains tattoos and worried looks are exchanged; the audience pulls together.

Between songs, between the hammer of Armand Majidi’s drummer, the thunder of Craig Setari’s bass on the left and Pete Koller’s guitar on the right, Lou’s playful banter is a highlight of the band’s performance, a series of remarks covering topics from Miley Cyrus’ recent appearance at the 2013 MTV Video Music Awards to the Black Flag reunion.

There is also a tale relating to the band’s first gig in London and a stand-off between the club’s gangster owners and the band’s German road crew over the cost of a microphone already broken before they took the stage.

Lou repeatedly asks the audience how they are holding up, waving a towel about to create a breeze that washes over the front row as Setari hands down a bottle of water to someone in the crowd.

More beer splashes over the crowd, our drunken friend returning to the pit before being carefully carried out again and a woman with dark hair, a white summer dress and a furious expression turns and raises both middle fingers in his direction, frustrated briefly at his stupidity.

She turns away again and heads back into the pit, slamming against men twice her weight with bare shoulders and raised fist, giving as good as she gets and never once faltering.

She disappears into the crowd, glimpsed only occasionally at the foot of the stage even as a whirlpool of shaven heads and sprinting feet carries others around one of several pillars dividing the ceiling from the ground.

The band tear through such tracks as World Full of Hate and Die Alone before also offering up a fantastic cover of Sham 69 standard Borstal Breakout in memory of a departed friend.

Towards the end of the night, Lou asks several times for fans to pause on their way out and visit a stand for charity TigerTime next to the merchandising tables and to not only sign up but also meet with members of the three bands – themselves, Knuckledust and Rough Hands – before leaving the venue.

One more song and a final encore follow and then it’s out into the Camden night, the streets lined by punks in the beerlight – to borrow a phrase from David Berman – and the last trains crawling up all aged rails towards Edgware and High Barnet.

When I talk about hardcore, I am invariably talking about bands such as Sick of it All.

When I talk about punk rock, I am talking about the solidarity of the disenfranchised.

And tonight the soundtrack of that unity rings like the echo of thunder still in our ears.

Jacob Milnestein