It's been seen before in this revered Dublin venue, of course, but centre stage in a packed, no-room-for-a-spare-sardine Whelan's, a lead singer is having a moment. The man in question is the charismatic heart of one of the most talked about bands in the country and he's likely soaking in two things as he lurches stylishly about, arms aloft, hanging from his mic stand and bashing off ceilings – his own amazement at the quality of the songs Leaders Of Men now have at their disposal, and the rapturous reception that they're receiving.

We're in the midst of a cold Wednesday night on Wexford Street, and Brian Ashe is coming to terms with his group's current situation. The Tallaght-based five-piece came out of the traps all guns blazing in March (apologies for the mixed metaphor that suggest a greyhound packing a pistol) and gained an instant following off the back of some incendiary performances and a debut EP. From there, they took on the competition and prevailed, winning the chance to play the Guinness Storehouse on Arthur's Day. The Whelan's gig is another milestone – first proper headliner.

"I got carried away there, sorry about that," smiles the amiable frontman in a velvet suit jacket. Perfectly understandable. The crowd, consisting of friends, family and true believers, seems to feel the same way. They're swept off their feet from the get go, as the five men clamber onto a stage that can barely contain them. Bathed in red light, they launch into 'Up Against The Wall'. Their signature at this point in time, it's also a slow build, adding to the sense of occasion when it finally erupts.

From there, the twin guitar attack provides jolt after jolt, as Ashe emotes with every sinew, gravel-crooning his way through the set. He's not the only one with some pipes – the guitarists lend their voices throughout, as does Dean Byrne on drums. Indeed, Gav Glynn takes lead duties as the night wears on, and wears it well. Solid new tracks are unveiled, giving notice that this is a band hard at work, and currently experiencing something of a purple patch. By now an old favourite, 'Bite Your Tongue' might be the stand-out, teetering atmospherically until Ashe can't keep schtum any more and lets roar.

Underneath it all is a rhythm section that could move mountains. It all gets a little tribal at times. Drums thud and reverberate laconically before turning into a flurry of hits, whilst Darren Lindsey plucks away understatedly and makes the room shudder warmly. It's music of restraint and release, music of a dynamism that dovetails perfectly with the frustration and yearning contained within the lyrics. The Walkmen are a self-confessed cornerstone of the sound, Hamilton Leithauser informing the melodies and vocal textures. Interpol in an Irish context, maybe, but Joy Division's territory isn't trodden too much. There's hope in these songs rather than claustrophic resignation, a sense of defiance in the face of dim prospects and hard days to come.

Today isn't one of them. This isn't trenchcoat warfare from the indie frontline, it's a celebration of achievement and a bit of a Christmas knees up. Leaders Of Men are comfortable in a sound that's building a fanbase, but clearly feel in themselves that they have plenty of higher rungs of the creative ladder to reach for. Room for improvement, and they're relishing it. Then the commercial aspect might follow. On the agenda for 2012? That debut album, plenty of kicking against the pricks and plenty of kicking out the jams. Let it lead.