After Roy Orbison finished his first number Thursday night at Mystic Lake Casino Showroom, a man in the audience shouted, "We love you, Roy." The crowd burst into laughter.

That broke the ice at the we're-not-quite-sure-what-to-expect hologram concert featuring early rockers Orbison and Buddy Holly, who died decades ago.

Something was needed to shatter the mood at this strange evening. This experience felt like neither a true concert nor a dramatic theater performance. It came across as some new high-tech hybrid that's, well, not quite ready for a prime concert circuit.

Surprisingly, the biggest problem was not the holograms.

Both Holly and Orbison looked remarkably life-like. You could see the veins in Orbison's hands (this was Traveling Wilburys-era Orbison), and Holly's pant legs moved as he shook his long limbs. With guitars strapped over their shoulders, they moved realistically and even turned and pointed to various live band members.

(One cavil: Holly's glasses didn't appear to have lenses, but Orbison's dark ones definitely did.)

The problems were the pacing and the execution.

Guided by Broadway director Eric Schaeffer ("Million Dollar Quartet"), the performance was divided into two 45-minute acts, with the stars alternating every four songs or so. In fact, once in the second segment, Holly offered only one tune and inexplicably exited. This disconcerting ADHD approach ruined the dramatic flow of the show.

The producers prepared smart, 3-minute retrospective videos on each Rock Hall of Famer, featuring vintage photos and performing clips, record jackets and interviews with famous people. For instance, Bono, Tom Petty and Jeff Lynne sang the praises of Orbison, and, for Holly, it was Don McLean (who coined the phrase "the day the music died"), Sonny Curtis (a Holly sideman) and Maria Elena Holly (his widow).

The Holly salute was broadcast at the beginning of the show before Orbison took the stage (huh?); the Orbison tribute kicked off the second act. The timing of both seemed odd. Why not show both at the beginning of the night?

Moreover, why not structure this like a typical concert: one act open, the other close? They could alternate nights, like co-headliners do at real concerts.

The other strange thing about having Holly and Orbison perform like tag-team partners was that they didn't literally walk off the stage.

No, these holograms either descended into the stage or disappeared into puffs of (visual) smoke. Yikes! Did Halloween arrive early?

The notion of holograms of late, great stars may be creepy to some people, but to make them vanish like ghosts was hauntingly bizarre.

One other technical complaint: the vocals – taken from vintage studio recordings – often sounded thin and tinny when accompanied by live instruments of contemporary quality. This felt like a sonic disconnect even though the two backup singers and five musicians (one player always mirrored what Orbison or Holly was playing on guitar) did a solid job. And, of course, the singing stars were spot-on.

Mystic Showroom was about two-thirds full for this new experience in entertainment. The concertgoers, mostly in their Social Security years, responded politely but rarely cheered as they might have at a bona fide rock concert.

The music volume was modest enough that earplugs were not necessary. There were no live video screens. Shooting of photos and videos was prohibited. And, of course, there were no meet-and-greets with the stars.

"I was impressed," said avid-concert goer Diane Lundahl of St. Paul.

She liked this hologram show better than a 2002 presentation of a concert movie of Elvis Presley on a giant screen accompanied by live musicians at the Minnesota State Fair.

"For $35, I got a good night of entertainment," she said Thursday.

Staged by a company called Base Hologram Entertainment, this concert used a different approach than the Eyellusion firm that produced last summer's Ronnie James Dio hologram show at the Myth nightclub in Maplewood. That process was more like an image projected onto a see-through screen; this one was a CGI technique similar to what the movies use.

Base is putting together a Whitney Houston hologram tour for next year, complete with dancers and a full band. That will be a giant leap – technically and emotionally – for the music world.