Going in, Saturday's sold-out concert by the Waterboys at the Fitzgerald Theater seemed like a perfect pairing of band and venue: elegant, old-world music played at an elegant, old theater that used to be called The World.

It certainly felt right for the first few songs, too. Frontman Mike Scott and his five bandmates kicked off the two-hour performance with "Strange Boat" and "Fisherman's Blues," both Celtic-flavored, bleeding-hearted, serene classics off the 1988 album "Fisherman's Blues," each of which shimmered gorgeously through the Fitzgerald. This was not a show where you wanted to order a last-minute beer when the house lights flashed the three-minute warning.

However, after a few more traditionalist-styled oldies ("A Girl Called Johnny," "We Will Not Be Lovers"), the venue seemed more and more ill-suited to what Scott had in mind. On his first U.S. tour in six years with a full band, the 54-year-old Scotsman made the most of his sturdy ensemble, turning rockier and feistier as the show wore on -- to the point where it felt like the gig should've been booked at First Avenue instead. Heck, by the time the band offered its downright punky tear through "Don't Bang the Drum" just before the encore, the Triple Rock even seemed like the right place for the gig, possibly with a mosh pit for those audience members without hip problems.

Instead, the sold-out crowd sat timidly through what were truly electrifying, hair-raising versions of "Glastonbury Song" and White Birds." Fans did finally stand up and sing along to "The Whole of the Moon," and they were back on their feet for the encore finale "Be My Enemy," which had the intensity -- and pretty nearly the same rhythm and chords – as Dylan's "Highway 61." Scott playfully tacked on Danny & the Juniors' "At the Hop" to keep the party rolling.

There were some moments in between that merited sitting and soaking in Scott's lush balladry, most notably the aged love song "You in the Sky," as well as the piano-plunked gem "Spirit." He and his lone heyday-era Waterboys bandmate of the night, fiddler Steve Wickham, played the Scottish/Irish traditional "Raggle Taggle Gypsy" as a duo – but even that one proved to be quite a rocking, riotous treat.

"Nice place," Scott said of the Fitzgerald, recalling his prior gig there in 1996 on a solo-acoustic tour. "I'm glad I'm back with my confederates," he added. So were the rest of us -- even those of us who felt confined having in our seats for such a truly thrilling, joyous concert.

Strange Boat / Fisherman's Blues / A Girl Called Johnny / We Will Not Be Lovers / Still a Freak / The Girl in the Swing / Song of Wandering Aengus / When Ye Go Away / Glastonbury Song / White Birds / If I Should Die Tonight (Marvin Gaye cover) / Spirit / The Whole of the Moon / I Can See Elvis / The Raggle Taggle Gypsy / Mad as the Mist and Snow / The Second Coming / Don't Bang the Drum ENCORE: Dunford's Fancy / You in the Sky / Be My Enemy / At the Hop (Danny & the Juniors cover)