Paramount marquee and Mike Flanigin’s 1974 Dodge Charger before “The Drifter” concert Sunday, Sept. 6, 2015. Photo by Peter Blackstock

“Did that just happen?”

Mike Flanigin was in a state of suspended disbelief Sunday night as he gazed across the Paramount Theatre stage, having witnessed Dallas soul-gospel singers the Relatives backing his childhood hero Billy Gibbons on the 1973 ZZ Top classic “Jesus Just Left Chicago.” It was a moment born of big dreams that rose from humble beginnings, the same process that begat Flanigin’s new album “The Drifter.”

Gibbons, the Relatives, singer Kat Edmonson and others had gathered with Flanigin on this night to celebrate the album’s recent release, and the live show proved to be an enlightening extension of the record’s considerable ambitions. Fleshing out the material from “The Drifter” with related revelations wasn’t really that hard once Flanigin arrived at this conclusion: “At some point I realized it was my own show and I just get to do what I want,” he told the crowd.

Running for two hours with a half-hour intermission, the concert brought the intimacy of Flanigin’s long-running weekend residency at the Continental Gallery on South Congress to a nearly full house in the city’s grand old theater across the river. Though the special guests got the marque billing, Flanigin’s world-class backing crew, led by musical director Charlie Sexton, was the bedrock: guitarists Derek O’Brien and Dave Biller, bassist Glenn Fukunaga, drummers J.J. Johnson and Kyle Thompson, and saxophonists Elias Haslanger and Scott McIntosh.

After two opening gospel numbers from the Relatives and a rare lead vocal from Flanigin on “Untouchable” (a song written for “The Drifter” that didn’t end up on the album), the musicians got their chance to shine on an extended variation of the album-opening instrumental “The Devil Beats His Wife.” Following the night’s theme, their rendition wasn’t an attempt to re-create the album so much as to expand its horizons. From Fukunaga’s pace-setting bass thumps early through fire-building solos from Biller and Haslanger to a final full-band crescendo, the stage reverberated with seven minutes of masterful jazz magic.

A perfect follower was “From the Dust,” another instrumental from the album but one that featured the graceful strains of the Tosca Strings quartet. They remained for the entrance of Edmonson, credited as the album’s executive producer; she delivered a gorgeous lead vocal on “Nina,” with a beautiful string break from Tosca in the middle.

Mike Flanigin at Deep Eddy Cabaret. Photo by Jay Janner / American-Statesman

Edmonson talked briefly about working on the album with Flanigin and explained that he’d been inspired during the process by the songs of Jim Croce. Flanigin previously had revealed he would do a couple of Croce’s songs at the show, but the surprise was that Edmonson sang them, to wonderful effect. The arrangements were a little ragged — the Tosca strings could have been more prominent on the exquisite ballad “These Dreams,” and backing vocals from Sexton and Flanigin got lost on the otherwise solid groove of “Working at the Car Wash Blues” — but the songs were excellent choices for bringing out the alternately tender and playful qualities of Edmonson’s voice.

The only real misfire of the evening followed with “Fit to Be Tied,” which closed the first set. A blues-punk burner with guests Clem Burke of Blondie on drums and Dominique Davalos of the Bluebonnets on bass, the song lacked the fiery emotion that Alejandro Escovedo brought to it on the record. Sexton and Flanigin together couldn’t quite match the spark of Escovedo, who was away celebrating his anniversary Sunday.

Also much-missed from his participation on the album was guitar great Jimmie Vaughan, who had a festival gig in Colorado, though O’Brien and Sexton helped fill that void nicely. And in an ideal world, it would’ve been nice to have Gary Clark Jr., whose album cameo on “Stop the World” was the lone “Drifter” track not played on this night, but Clark is busy with obligations for his own highly anticipated new record due out this week.

The presence of Gibbons, who on Saturday had played in the city of La Grange with ZZ Top for the first time ever, ultimately was more than enough to cover those absences. When the lights went up on the second set, Gibbons and Sexton appeared together at center stage to a great ovation, and as Gibbons introduced the title song of “The Drifter,” the band caught fire amid a swirl of red lights and smoke.

They kept the momentum with ZZ Top’s “She Loves My Automobile” (from 1979’s “Deguello”) and a blazing cover of Jimi Hendrix’s “Foxy Lady” before the classic moment of the Relatives backing Gibbons on “Jesus Just Left Chicago.” Gibbons subsequently departed as the Relatives’ Rev. Tommy West took center stage to talk about his older brother, the late Rev. Gean West, who’d recorded a classic recitation on the “Drifter” track “Tryin’ to Make My Way Back Home” before his death earlier this year. Tommy reworked that recitation into a moving tribute to Gean, with the instrumentalists and singers providing soulful support behind him.

Nearly everyone then came back to the stage for the finale, the album’s swingin’ celebration “All Night Long.” Solos passed from Sexton to Gibbons to O’Brien to Haslanger to Flanigin as Edmonson and the Relatives gloriously swooped and swayed to the rhythm and blues.

A sweet encore featured Flanigin and Edmonson’s acoustic-guitar-and-vocal heartbreaker “Someday” and, finally, the instrumental “This Life,” the core players rejoining to bring it home. The lights went up and the audience beamed in the glow of a very special night, lingering in the lobby and out on the street where Flanigin’s trademark 1974 Dodge Charger was parked in front of the Paramount marquee. No one seemed to want it to end, so many found their way across the street to the Townsend, where it looked like the party might continue, All Night Long.

Mike Flanigin and Kat Edmonson (in light at right) with “The Drifter” band at the Paramount, Sunday, Sept. 6, 2015. Photo by Peter Blackstock