George Strait didn’t need to spend much energy to thrill the lucky few who made it inside Gruene Hall for his hastily arranged, invite-only gig Wednesday night. The treat was in the setting, the storied dance hall that he and his Ace in the Hole Band played monthly when they were coming up in the late seventies. And it was in the intimacy of the evening, a crowd of some 300 people pressed against a stage barely two feet off the ground. For an hour and a half Strait gave them exactly what they’d hoped for, running through an abbreviated version of the handful of Las Vegas shows that have comprised his semi-retirement. He played hits from throughout his career, from “Marina del Rey” to “Check Yes or No” to “Give It All We Got Tonight.” He debuted two new songs that sounded instantly familiar, “Kicked Outta Country” and “You Gotta Go through Hell.” It was all classic Strait.

But then he dug a little deeper. Maybe it was being so close to the audience that he could feel them respond to the opening notes of each song. Or maybe it was seeing his players occupying the exact same spots on stage they used to man forty years ago. Or maybe it was whatever he had poured into the red Solo cup he periodically nipped on. At one point he joked it was milk. “Two-percent,” he insisted.

Whatever it was, when he huddled with the band in the vestibule outside the men’s room waiting to reappear for his encore—Gruene Hall famously has no dressing room—he looked at his musicians and called an audible on the set list. Instead of “I Saw God Today,” a power ballad about faith and fatherhood, he wanted a barnburner. “Let’s do ‘Take Me Back to Tulsa,’” he said. The band took the stage and tore through the classic Bob Wills western swing number like they wouldn’t get paid unless everybody in the room danced. I was at the show with Bruce Robison, the Austin singer-songwriter who has seen Strait take two of his songs, “Wrapped” and “Desperately” to the top of the country charts. When “Tulsa” was over, Robison turned to me and said, “Man, we’re going to be boring our kids with stories about how we saw George Strait sing that song, here, for the rest of our lives.”

Judging from the forest of longnecks hoisted skyward, the sentiment was shared, though the crowd wasn’t a typical dancehall audience. The show was what Music Row professionals call a “media event,” a private party for industry insiders to generate enthusiasm for new product, which in this case is Strait Out of the Box, Part 2. Released today exclusively through Walmart, it’s a three-disc, fifty-six song collection covering the twenty years since Strait’s first box-set, and it contains 36 singles, eighteen of George’s Choice album cuts, and the two new songs he played in Gruene. Strait also took the occasion to announce a new twist on his residency at the MGM Grand Las Vegas: Four weekends’ worth of shows in April 2017, in which he’ll play all sixty of his number one hits—the most of any recording artist, ever—half on Friday nights and half on Saturday.

So among the 300 invitees were radio hands from around the country and label execs from Nashville, plus other guests intended to lend to the buzz, like Strait’s Universal label-mate Jon Pardi, Texas Country artists Aaron Watson and Kyle Park, and pro wrestler the Undertaker. But mixed in were family and friends of Strait and the band, and the night maintained the distinct air of a homecoming. His wife, Norma, sat in her customary spot near the back of the hall, shelling peanuts for their four-year-old grandson, Harvey. Strait’s son Bubba, whose name was called frequently from the stage when his dad introduced songs that they’d written together, bounced back and forth between catching up with other songwriters and holding Harvey up to see the stage. And outside, some 500 true believer Strait fans who had caught wind of the show online gathered by the old hall’s turned-down clapboard windows. Some shot videos on their cell phones, others two-stepped in the grass.

It was Strait’s first show in Gruene since a two-night stand in July 1982. He was already a national act by then, but his first number-one single, “Fool Hearted Memory,” was still working its way up the charts. The audiences that weekend were the dancing couples he’d been playing to for years, and his band got dressed before the show in the parking lot, just like they always had.

There was something of that on Wednesday. When the band blazed through his typical second-to-last number, “Folsom Prison Blues,” Strait wasn’t able to walk from musician to musician as they soloed like he does when they play in the round in arenas. Instead he stood at the mic and flashed a genuine grin. I had the distinct feeling that even if he hadn’t spent the last 34 years selling more than 70 million records and touring the world, he’d have been playing Gruene Hall on this night anyhow.