When Reba McEntire and country duo Brooks & Dunn first announced their Las Vegas residency at Caesars Palace in December 2014, it was planned as a short-term thing, with only a handful of dates. Kix Brooks and Ronnie Dunn had dissolved their musical partnership in 2010 and were just taking tentative steps toward reuniting. The three-way team-up was an experiment for all, although McEntire and Brooks & Dunn had toured together twice before, and it might not have stuck.

Cut to three and a half years later, and Together in Vegas is a staple of Strip entertainment, with McEntire, Brooks and Dunn joining the likes of Celine Dion, Elton John and Shania Twain at the Colosseum. The trio returns for its latest round this month, making it the longest-running country show on the Strip. The two veteran acts have dozens of hit songs to choose from, and the two-hour show includes chart-toppers from both, performed with members of their backing bands.

Along with their hit collaborations “If You See Him/If You See Her” and “Cowgirls Don’t Cry,” the show includes some of the most popular songs from McEntire (“Whoever’s in New England,” “Is There Life Out There,” “Fancy”) and Brooks & Dunn (“Brand New Man,” “My Maria,” “Boot Scootin’ Boogie”). The three performers share the stage not only during their well-known duets, but also throughout the show, creating an ebb and flow that’s emblematic of a true collaborative effort.

All three performers have kept themselves busy over the course of the residency. Dunn released his third solo album, Tattooed Heart, in 2016, and Brooks hosts Steak Out on the Cooking Channel. In 2017, McEntire released a gospel album, and she has taken on perhaps her oddest project yet as the latest star to portray Colonel Sanders in KFC’s television commercials.

Whatever other projects they may be working on, McEntire, Brooks and Dunn seem more than happy to keep Together in Vegas going. As the show has become more established, the trio have gotten into the Vegas groove. “Vegas is great,” Dunn told Taste of Country when promoting Tattooed Heart. “We took in a bunch of shows. We went to Jennifer Lopez’s birthday party. There’s always something going on.”

As McEntire told Rolling Stone when announcing yet another extension, the show provides an outlet for them as artists. “It keeps us curious: What songs can we trade out and make it more interesting for the band, the crew, for us and the fans?” she said. “Because if we’re bored, they know we’re bored, so we keep it interesting.”

Caesars Palace, 7:30 p.m. March 21 & 23-24, $59.50-$205 plus tax and fee. 888.929.7849 AXS