The rise of The Gloaming has been a shock. This shaggy traditional 'supergroup', fronted by violinist Martin Hayes and Irish-language singer Iarla O Lionaird, had a surprise hit with their debut album, top-seller at Dublin's Tower Records last year.
How did the capital's hipsterati come to fall for what is a mostly conventional trad LP, with its fiddle fugues and troweled-on Celtic ennui?
On the first of an Ed Sheeran-esque three-night run at NCH, the answer proved endlessly elusive, though it was fun to theorise as the music gusted over you.
With American producer and arranger Thomas Bartlett on piano, Dennis Cahill on acoustic guitar and Caoimhín Ó Raghallaigh augmenting Hayes' florid fiddle with his more stripped-down style, the band delivered upbeat jigs and moon-eyed laments, all lapped up by a room that fairly swooned from the off (and which included the President and his wife).
The set divided between 'work-in-progress' newer compositions and material from the album (among the favourites for this week's Choice Music Prize). All of it was defined by an acutely self-aware sensibility that split the difference between something you might encounter in a Doolin pub in high tourist season and the soundtrack to Ken Burns' American Civil War documentary (Hayes' violin runs, especially, evoked that series' mournful theme, Ashokan Farewell).
Throughout, the ensemble provided a study in contrasts. Seated at a low table, O Lionaird occasionally smiled but mostly had the air of a bank manager about to turn down your request for a loan. To his left Bartlett fairly swooned over his piano in a fashion that sometimes felt over the top, especially as his overwrought body language was in contrast to his subtle tinkling.
The beating heart of the outfit, Hayes, meanwhile, augmented his playing with jaunty foot-stomping. This was mostly met with awe-struck solemnity by the audience. He may have preferred if people had clapped along, as might have happened at a session back in his native Clare.