It's a Sunday night, and people are dancing in ways I've never seen before. Having found our way to Hoxton Basement's unassuming doorway, we're directed through a huddle of bouncers and down the stairs. Pushing open the doors onto a still-sparse dance floor, no one notices us arrive. For the most part, they're too busy moving. Throwing full-on footwork, spins and leaps, there's an energy in the room that's rare to find—especially for 8 PM.

The serious dancers are in the middle of the red-lit room, which has speakers in each of the four corners. The less aerobically-inclined are spread out across the back and sides of the room. More mellow but dancing with the same uninhibited spirit, people groove freely on the spot, grinning and enjoying themselves.

The loose, syncopated sound of broken beat is the backbone of the night's music. DJs' sets deviate toward garage, bossa nova edits and beefed-up drum workouts, all the while maintaining that same high-energy feel to the music. Toward the end of his warm-up set, IG Culture, one of the night's residents, cofounders and its de facto MC, gets on the mic to welcome people in and to remind them to stay hydrated. It's good advice: by the night's close at midnight, most people in the packed room are dripping with sweat.

It's an older crowd, and there's an unpretentious, infectiously good-natured atmosphere. Later in the night, a circle opens up for dance-offs. The energy levels are kept at a level that leaves me completely exhausted by the end. From the 50-somethings, who are likely long-time devotees, to the younger attendees like ourselves, it's a mixed, open-spirited party that feels hard to describe without drifting into "all under one roof raving" clichés.

As I learn from speaking with some of the party's founders, this warm, welcoming atmosphere has been a part of CoOp from its early days. CoOp returned in March of this year after a ten-year absence, following two Boiler Room broadcasts that inspired the idea to bring back the club night proper. The Boiler Room shows were in December of 2015 and 2016, and since the first party in March there's been a new EP on the party's label and three more editions of the night, including this August's return to Hoxton Basement.

The hub of London's early-2000s broken beat—or simply "bruk"—scene, CoOp was started in 2000 and ran until 2007. Founded by Dego, Demus, Phil Asher and IG Culture, the residents shifted and evolved, with members of Bugz In The Attic—the nine-strong production group, whose remixes helped to define the bruk sound—trading places with the founding four. Running every other Sunday night, it was a testing ground for new, forward-thinking music whose counterpart, on the other two Sundays of the month, was the much-storied dubstep incubator FWD>>.

Started at the Velvet Rooms in 2000, CoOp moved to the legendary Plastic People around 2003. It developed a loyal crew of regulars who'd come to hear fresh music and, increasingly as the night went on, to dance with some serious flair. The sound was shaped by UK club cultures that had come before it—the crate-digging schools of rare groove and hip-hop, the dancer-fuelled explosion of acid jazz, and the breaks-mangling, sub-rattling experiments of jungle.

From the founding figures who went their separate ways in 2007, it's IG Culture and Alex Phountzi from Bugz In The Attic who've now picked up the baton. After reconnecting in 2013, they started to meet up every week or so to work on music. Their new moniker, NameBrandSound, was a catalyst for both of them to start making tunes again. But it was also a reminder of what they were missing: the appreciative, up-for-it crowd audience they used to count on. They'd occasionally discussed the idea of bringing CoOp back, but it was the Boiler Room shows—and people's appetite for them—that pushed them to actually do it.

A few days before the most recent party, I sit down with the pair in a busy Hoxton pub. With the unspoken dynamic you'd expect of such old friends, they tend to answer questions between them. IG, the older of the two, answers with a brusque, muted assurance, responding with short, to-the-point answers. Phountzi, more considered, unravels points or quibbles the details.

They're both clear that this second phase isn't about nostalgia. "A lot of people are asking us to do a regular night," IG says. "But we're trying to build it strategically, because we need everything in place. We need the label in place for the stream of music to start coming, because there's no point in us doing a retro night."

"We need to build up a head of steam in terms of music coming out," Phountzi says. "So suddenly it's like, whoa, there needs to be a place to hear this music regularly."

The new label, CoOp Presents, is going to focus on music from new producers. It arrives along with Selectors Assemble, the tag that IG uses to refer to the growing network—made up of people like Aly Gillani, who runs the First Word label, and Boiler Room programmer Errol Anderson—who help them release music and throw parties.

Bringing the likes of Anderson (who also DJs as Andwot) into the fold, they've built a new core of younger DJs who play at the parties. Making those links, they explain, is vital to what they're trying to achieve. "It's about a lineage," IG says. "It's coming back and we're bringing people in who are part of the same line. It's experience teaching the youngers and the youngers giving us energy."

Having seen Shy One at Hoxton Basement, it's easy to see what he's talking about. Threading together Rhodes-jamming broken beat with grime-tinged percussion tracks, she tapped into that heritage in a way that's facing firmly forward. A regular presence at the parties since the Boiler Room in 2016, the 20-something producer and DJ was connected through Errol Anderson.

Speaking on the phone the following week, she remembers how she had to leave the party for another booking that night. "I was gutted that I had to tear myself away," she says. "The other one was a much bigger party, it was gonna be hype... But I just knew it weren't gonna nearly touch what was happening at CoOp. I love that it attracts dancers, proper old jazz dancers. And the people are friendly, they're lovely."

Both of us are too young to have attended the parties first time round, but we agree on how different an experience the new parties are to any of the nights we've been to. "It's ironic that an old kinda club vibe is some new, amazing thing for us," she says. "But it's the best."

EVM128 is another regular figure at the rebooted parties. Sporting long hair, a baseball cap and baggy jeans, he takes a quick-mixing, ruff 'n' tuff approach to his sets. At both the parties I've been to, he's jumpstarted the energy more than anyone else. Contrasting heavy-hitting rhythms with lush, jazz-tipped chords and vocals (which are, arguably, the sounds most evocative of the broken beat style), there's a similar sense of a lineage being reenergised.

EVM has also become involved behind the scenes, helping to organise the nights and the label. He was a regular dancer at the parties throughout their Plastic People days. Working in Soho at the time, he spent lunch breaks buying second-hand hip-hop at Reckless Records. A friend there showed him the records that were emerging from the bruk circle. EVM went to a night where Seiji from Bugz In The Attic was playing. Drawing some of the crowd who would also go to CoOp, the vibe immediately stood out. "It was just like, 'Rass, what is this stuff? This is too bad.' That really caught me," he remembers. From then on, he would go to the Plastic People sessions religiously.

"It's literally just about dancing," EVM says. "It sounds cheesy but you can feel the happiness in the room. Everyone's so friendly, no one's stush, it's not about what you're wearing. Everyone gets down there early, 'cause they know it finishes at 12. Within an hour of the doors opening, everyone's in and dancing."

For EVM, there are only a couple of other parties in London that embody the same ethos: the Eglo label nights run by Alex Nut at Corsica Studios and Benji B's Deviation. "They're dope, man. They're quite similar to what you would have seen down at Plastic People." It was a connection to Alex Nut that led to another emerging strand of CoOp's new iteration. He put them in touch with Henry Wu, the keys player, producer and DJ who, off the back of his now-split band, Yussef Kamaal, is helping to organise a night of live versions of classic CoOp tracks.

Shy One, IG Culture, Mark Force, Alex Phountzi, K15, Henry Wu, Adam Rock

IG Culture says that CoOp originally came from a need to build a crowd who were into the style of music they were pushing. "We got to a point where we never had a place to play the music," he says. "People were booking us to DJ, but there wasn't no such thing as broken beat, so we was getting booked in places where people didn't know what we were doing."

In turn, starting the night pushed the sound in certain directions. As Phountzi recalls, placing the producers face-to-face with audience reactions honed their approach. "Before the night, it was very freeform in terms of different tempos," he says. "For a lot of the stuff we were doing in the Bugz camp, we weren't really going out, we were just hanging out in the studio. So there was a number of different styles, and I think after CoOp started a more dance floor-style definitely started to emerge."

Around the same time as the party started, the compilation Co-Operation Volume 1 sprung up. Informed by a collaborative spirit, many of the artists took on short-lived monikers, like Dego's Pavel Kostiuk or IG's Murky Water. Trading ideas or melodies in each other's tracks, the group's different backgrounds meant that shared studio time could mean trading skills—the virtuoso keyboard playing of Kaidi Tatham, or the hardcore production chops of Dego.

This all solidified a likeminded approach that had been gestating in the group for years. Coming from the hip-hop duo Dodgy City Productions in the early '90s, IG had started to release his own music on the People label he'd cofounded in 1997. Dego, who'd been co-running the seminal jungle and drum & bass label Reinforced Records from the early '90s, was starting to hint toward a similar direction in his productions as part of 4hero.

Phil Asher, who'd been DJing in London clubs from the early '90s, was taking his UK house background in a looser, broken-styled direction. And Demus was a recording engineer who'd worked on records for the likes of Young Disciples, the acid jazz group who, like Dego, had been signed to Gilles Peterson's Talkin' Loud label.

Goya Music also became an important part of this scene. The record distributor helped with production and distribution deals for the various newly-formed labels, and also made the connections to get the records onto the racks of shops. Started in 1997 by Mike Slocombe and Spencer Weekes, their offices were at the Saga Centre in Kensal Rise, West London. Right in the thick of where most of the CoOp circle were based, the location made them a day-to-day meeting place for the group. Goya eventually renovated the office's derelict basement, using it to build studios that were rented by the likes of IG, Phil Asher and Bugz In The Attic.

As time passed, the makeup of the crowd at CoOp began to change. At Velvet Rooms it was mostly serious-minded record heads, faced-forward at the DJ booth all night long. Later, as they moved to Plastic People, a core of dancers began to emerge alongside the heads. The idea of a diehard crowd of regulars is often linked to Plastic People, but the dance-off circles are something that seems to have been more specific to CoOp. From early on, Gary Nurse, who'd been part of the early '80s jazz dance crew IDJ, was a regular, drawing a line between the declining jazz dance scene and CoOp's MPC-powered workouts. The style of dancing might have been different, but CoOp was seen as a cousin of a dance culture that had once been widespread in the UK.

The dancers would often arrive first, making the most of the free space. As it filled up later on, they'd shift to the space between the bar and the dance floor. The anything-goes feel at the start of the parties often attracted a whole range of people, including, as IG recalls, a troupe of rollerskaters, who were on a visit from Amsterdam.

The focus of the music was upfront selections, the core of which was new tracks from the CoOp circle. But they also drew from elsewhere, in particular hip-hop and garage. "At the time, it was never a case of, 'Oh, we're just gonna play broken beat,'" IG explains. Instead, "We said, 'OK, nothing before '99.'"

K15, another of the new recruits old enough to have been part of the group the first time round, recalls how his first visit to the Velvet Rooms upended all of his expectations. He was part of a busy community on the online message boards for 4hero and Bugz In The Attic, and spent plenty of time there posting and deliberating over new music, but building up a narrow idea of CoOp. "I remember when I was going I had in my mind, I'm gonna hear all this broken beat music," he says. "I got through the door and they were just playing hip-hop records by Black Sheep... That was my first time hearing a load of Dilla instrumentals out loud, or hearing brand new music by Sa-Ra. The vibe in there was so crazy, and it just made me realise you can play whatever you want."

That connecting-the-dots approach has since become a quality that's evident in K15's productions. With boogie-influenced basslines often laced through house tempos and swung percussion, his DJ sets also span hip-hop, house and Brazilian music. It's a bedrock of influences that comes up repeatedly in conversation with the others I speak to.

"It's a London heritage," IG says. "In the jungle scene, you had big tunes with rare groove samples. That's what we grew up listening to: rare groove, dancehall, reggae." Along with US-imported hip-hop and house, those different threads have continued to influence the music, whether it's absorbed and reimagined in new ways, or sitting side-by-side in DJ sets.

Shy One sees a reverent attitude toward the music's roots as the connecting thread between those who, like her, are drawn to CoOp. Taking K15 as an example, she says, "I reckon if you got him to whittle it down to what his favourite records are, or what his biggest inspirations are from older musicians, they'd be jazz artists." Name-checking Henry Wu, she says, "I think it comes from that respect for older musicians and older styles of music. And jazz, which is at the root. Before hip-hop and soul, it's jazz. It's that love of musicianship."

This mindset seems suited to making music that moves with the times. A prime example is the Selectors Assemble EP, the five-track compilation released earlier this year. Bringing some of the old-school producers (plus Henry Wu) back together, it sounds like their styles have been rewired with recent musical developments in mind.

This malleability is perhaps rooted in the scene's unrealised possibilities. Broken beat never crossed into the mainstream, which left a legacy less weighed down by the baggage of other UK club styles that exploded. There was never a breakout artist or track, which meant that the sound was never co-opted by the pop machine, or drilled down to a fixed, restrictive style. The lack of success might have led to things fizzling out when CoOP closed in 2007, but it also left distinct musical strands that were ripe for later development. Breathing new life into those ideas, the style that's emerging hints at a genre-blurring, bass-heavy attitude, strongly shaped by the UK's melting pot of club sounds.

"When you look back on it now, things were popping off every three or four years," Phountzi says. "Very new and distinct forms of electronic music were coming out of the UK, out of London or Bristol. I remember at the time thinking, sometimes maybe we're moving on from some of these good ideas too quickly. Orin [Afronaught] always used to say, 'This is just the blueprint now,' and I guess he was right."

Mostly restricted to a small, dedicated crowd of producers and listeners, the hiatus period has allowed time for people's influences to gradually drift outwards. Prices for the records have begun to creep upwards on Discogs. And labels like 22a and Eglo have been nodding to the legacy with both bruk-influenced newcomers as well as old hands like Dego & Kaidi.

CoOp's comeback could have been as short-lived as it was backward-looking, serving up throwback tunes, comforting nostalgia and little else. Sure, there's been some reminiscing: classic tunes have been played at both of the nights I've been to. But with the new faces welcomed into the fold, there's a whole range of ideas for which directions the music might take. "I wanna be in a situation where we don't even have to turn up to the dance... just leave them to do it," IG laughs. "Pass the baton, ya know what I mean?"

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