AT THE pub in the back streets of London’s Kentish Town, The Bluetones — due to play at the Forum across the road — are at the next table.

It’s as good way as any of knowing that a band aren’t due on stage yet.

The Bluetones are back. Had they ever gone away? The answer is yes, sort of. For a bit. They split up four years ago, slightly aggrieved to see their fan base return for their nostalgia-laced farewell tour.

“Where the hell have you been for the last 10 years?” the singer, Mark Morriss, chided at the time.

Since then Morriss has been embroiled in a solo career but he missed his bandmates, so they often turned up on stage with him. Mark Morriss, playing Mark Morriss songs and the occasional Bluetones cover, with his backing band, The Bluetones.

This time, they’re back properly, to mark their 20th anniversary and the thirtysomethings and fortysomethings are out in force, ready to sing that one that goes: “You don’t have to have the solution you just got to understand the problem,” and the other one that goes: “Na, na na na na, na na na na na, na na na na na, na na na na, na na na na.”

When they play songs from their later, post-Britpop oeuvre, the mood changes. Lads go to the bar, or chat, or check their smartphones to see if someone has liked something they’ve said on social media in the past hour.

It’s a shame, because they’re missing some crackers. Never Going Nowhere still sounds like a lost classic, its huge delayed chorus of Motown proportions. The couple of dozen people who bought it go justifiably crazy.

Tiger Lily from third album Science & Nature is a gorgeous, gently lilting song of late-night phone calls and doomed long-distance relationships.

“Would you like us to do a new album?” Morriss asks from the stage, half an hour in. There are cheers but not of the full-throated variety.

“Good, because the next six or seven songs are new ones.” More cheers, but nervous ones, interspersed with knowing laughter. He’s joking — but he’s not. In the latter half of their career, The Bluetones produced some of their best material, heartfelt and gorgeous tales of love, heartbreak and devotion.

But the band’s time was done and no-one was listening any more. It must have been exceptionally frustrating for them but give the band credit: they play those songs anyway, they just don’t see the point of releasing anything new.

“We were worried how this might come across but then we thought, this is our train set. It’s up to us if we want to have a play with it,” Morriss admits/justifies half-way though. He’s talking to himself as much as anyone.

The ravages of time seem not to have affected the band too much. Bassist Scott Morriss is dressed as an X-Wing pilot out of Star Wars, for reasons that are never explained. He lives in Japan now, so perhaps he flew in for the gig.

Adam Devlin, guitarist and latter-day Twitter troll, looks slightly owlish in his glasses but he’s still a picture of louche amusement as he wiggles his way through the solo of gorgeous set-closer Putting Out Fires. And the singer can still shuffle and hit those notes like the best of them.

In the encore, they please themselves. Ancient B-side Teenage Jesus gets an airing, to widespread bafflement, as does a cover of the Minder theme tune. But they’re only teasing. They close on If…, source of all those “na na nas,” to leave the crowd hugging, singing and bouncing all the way back to the Tube.

“Not bad for one-hit wonders,” Morriss enthuses towards the end.

Pointedly.