Ballerini will play her hit duet "This Feeling" alongside the Chainsmokers during the special, which will also feature artists such as Dua Lipa, Ella Mai and Charlie Puth.
While some country stars may not be able to leave their homes without sunglasses and a baseball cap on, lest they be spotted by fans or paparazzi, the tables turn on Halloween.
Before Kelley was part of Grammy-winning country trio Lady A, he and his older brother Josh were in a country rock group, and their first-ever record deal was offered by none other than the Godfather of Soul.