Such was the situation Friday night for the Boston debut, and second US date, of the Dublin quintet Hothouse Flowers, at the soldout Paradise. Stardom is a dicey thing to predict, a crapahoot at best - and too many notables have fallen by the wayside - but there's no rational reason why Hothouse Flowers shouldn't - um, sorry, this is the only play-on-words - blossom and bloom.

During their 1OO-minute set, there were quiet pauses and reassuring, raucous blasts, heart-wrenching lyrics and bar-band, party-hearty guitar chords, an a cappella vocal treatment (the traditional Irish ballad "Carrickfergus") and saxophone-led sprints into the stratospheric heights of rock 'n' roll heaven.

If you're into influence and lineage, you can hear the Celtic side of Dexy's Midnight Runners or, further back, the R&B-stoked fires of Van Morrison's Them. That's fine, and it's accurate. If you're simply looking for - and this is a key idea - creditable optimism, you've also come to the right spot. The Flowers' lead singer-pianist, Liam O'Maonlai, has it figured out. "If you're happy," he said, introducing a new song of that title, "you've got to sing about it." His band's delivery made sure there was no argument.

Consider, also, the depth: In the group's second song, "The Older We Get," the long-haired, bearded, sandal-clad O'Maonlai sang not of first lust - the rock standard - but of enduring love. "The older we get, the further we see," he sang. "The more we mean to each other, the more you mean to me." All the Flowers crafted a delicate, yet power-packed, crescendo-spiked song. It had a breathtaking emotional and musical sweep. And, of course, there was much more to come. This was just the first of a 17-course feast, in which all musicians and members of the audience were welcome. (Well, save the two guys who got tossed out after jumping on stage and flying Ireland's flag during "Ballad of Katie."

Hothouse Flowers, like most good things Irish, are touted by their pals in U2. An obvious connection can be made in terms of hope and urgency. The Flowers don't, though, employ the ringing guitar sound and aren't as overtly spiritual - meaning (thankfully) they're not U2-2. They do sing of commitment and trust; they imply, on stage and through lyrics, a sense of brotherhood and bonding.

A sampling of stuff: "If You Go" (an encore standout and emotional tussle), "I'm Sorry," and "Don't Go," their hot radio hit, all rang true; all seemed born of genuineness, warmly conceived, and heated to the proper temperature.

Enough superlatives already - Hothouse Flowers are worth your attention and investment.