If you thought Chris Stapleton, Morgane Stapleton and Anderson East's cover of "My Girl" couldn't get any better -- well, you'd be wrong. On Wednesday night (April 27), the three artists added country superstar Miranda Lambert to the mix, taking the already-stellar song up another notch.

Readers can press play above to watch the performance, which took place at Los Angeles' Greek Theatre. The video begins with East leading Lambert, his girlfriend, out from the stage wings to enormous cheers and applause from the crowd. Chris Stapleton begins the song as East, Morgane Stapleton and Lambert groove along to the melody. East leads the second verse, while Lambert and Morgane Stapleton add harmonies throughout.

The Stapletons and East performed "My Girl" -- a No. 1 hit for the Temptations in the mid-1960s -- during their Berkeley, Calif., tour stop on Saturday (April 23), but Lambert's added star power was clearly welcome in L.A. Morgane Stapleton greeted the singer with a hug when she hit the stage and gave her another one before she walked off.

Previously, East and Lambert shared a stage (again by surprise) on Valentine's Day (Feb. 14). Lambert surprised the crowd at East's show in Northampton, Mass., by adding harmonies, along with Gwen Sebastian, on a cover of Mariah Carey's "Always Be My Baby."

The Los Angeles show was Stapleton's first after postponing a Tuesday night (April 26) concert in Santa Barbara, Calif., because he'd lost his voice. The Santa Barbara show was the only one he canceled due to the issue.

Stapleton has a busy summer coming up: He recently released new single, “Parachute,” from his debut album, Traveller, and he’s booked to play Bonnaroo in June. He and Hank Williams Jr. will also be joining forces for a co-headlining tour that runs throughout August.

Learn the Story of Chris Stapleton's "Nobody to Blame"