Ultrasonic Rock Orchestra — 18 singers and eight instrumentalists — started the first of their three nights of “A Night at the Rock Opera” last Thursday at Arlington’s Regent Theatre with Queen’s “Tie Your Mother Down” and closed with five more Queen tunes that included a rapturous “Bohemian Rhapsody” and a properly martial and triumphant “We Will Rock You/We Are the Champions.” The rest of the show featured songs from “rock operas” (Tommy, Jesus Christ Superstar) and story-song non-operas like the Beatles’ “Paperback Writer” and “Sgt. Pepper’s Lonely Hearts Club Band/With a Little Help from My Friends” and David Bowie’s “Space Oddity” and “Starman.”

There was no acting and no attempt to create thematic continuity. URO simply culled nuggets from the pompous heyday of grand, glorious classic rock and added massed vocals for operatic effect. The one exception was a four-song mini opera that kicked off the second half of the night, a thing called Will We Rock You? that URO producers Sal Clemente (vocals, MC) and Alan Ware (drums, acoustic guitar) wrote with singer Peter Montgomery in response to Andrew Lloyd Webber’s refusal to grant them the rights to make a film about reviving Jesus Christ Superstar. It worked. They nicked the right major-chord progressions and stylistic transitions from the big guys. They mocked Sir Andrew and celebrated with lines like “We’ve got to make something of this mess/Turn this tragedy into success.”

Was it bombastic? You bet. Rock opera is one genre where that’s a compliment. And the singers were decked out like a punk/goth version of a Rent cast.

Clemente noted from the stage that the show would have its “ups and downs,” and that was true. The lyrics to “Pinball Wizard” got scrambled once, and not all of the dozen odd lead vocalists were on the same level. (Andrew Kuhn, Rod Eymael, and Fatima Elmi stood out.) But it was the majesty of the harmonies that carried the night, especially on the three-song finale of tunes from Tommy. URO will bring “A Night at the Rock Opera” into Boston for a one-night performance at the Berklee Performance Center this Friday, November 17.