You can’t keep anything a secret these days – not least, it would seem, the Saturday sunset slot on the main stage at End Of The Road this year, which has been billed as “???” all weekend but which by Saturday morning even hitherto uncontacted tribes in northern Brazil know is going to be Wet Leg. Still, when the band’s onstage branding is revealed a couple of minutes before they appear, the scream of excitement is unlike any other at this year’s festival: it’s young, hysterical, raucous and completely fannish – in other words, a world away from the traditional End Of The Road archetype.

And thank god for that: after all, at this point in their meteoric rise, with more backlashes to backlashes to backlashes than can be counted in a hall of mirrors, the fact is that being down on Wet Leg, or even just sceptical, is just a really fucking boring opinion. They may be overexposed and trading on a single album, exploiting the hype machine for its every last fume, but so were The Strokes in 2001. Shit, so were The Beatles in 1963. Sure, nobody’s expecting them to follow either of the above’s subsequent trajectories, but it doesn’t reduce the joy of the moment and the sheer glee of having insanely hooky, funny, giddy pop songs played right there in front of you, all singalongs and clapalongs and whoopalongs custom designed to make your heart beat just a little faster.

It feels pretty clear that Wet Leg know all this too: “Hi, we’re Oasis”, they offer as a greeting, before launching into ‘Being In Love’ and then rattling through most of their debut album, pausing only to reveal, rather touchingly, that it was on the ferris wheel over in the site’s woods, four years ago to the day, that they decided to put together a band. No one quite has the gall to call this set a homecoming as a result, but the fact that that fairground ride birthed a double-Grammy-winning project that’s now being directly mined by arguably the world’s biggest pop star is a testament to the magic that this festival seems to conjure.

Least surprisingly in a “surprise” set already low on surprises, they end with ‘Chaise Longue’, the biggest crowd of the weekend shouting back every last word in unison until they’re hoarse, and it’s all just a blast. Ten songs, 45 minutes, back on the bus and probably halfway home by the time Future Islands are tearing the same audience an emotional new one on the same stage an hour later, there’s a joyful sense of what-just-happened to Wet Leg’s appearance, a blink-and-you’ve-missed-it energy despite all the terrible secret-keeping, and the festival momentarily becomes slightly more electric because of it.

End Of The Road frequently feels like a massive house party, with its incredibly loyal patrons, who come year upon year regardless of line-up, as the hosts, and the musical line-up as invited guests. From that perspective, perhaps that makes Wet Leg an unexpected gatecrasher this year – but when the gatecrasher rocks up with this much sense of entertainment, the only sensible option is to lean right in.