Decked out in all-Idol wear – sunglasses and pants emblazoned by the singer's name as well as a cutoff black tee and leather jacket with Idol's face – Cyrus sauntered out from the side of the stage midway through the set to "sing with Billy fucking Idol. Let's do it!" Idol handled the single's first verse, with Cyrus taking over on the second verse.
Idol's four-song IHeartRadio festival set kicked off with his hits "Dancing With Myself," "White Wedding" and "Flesh for Fantasy" before Cyrus, who was not listed on the festival's all-star lineup, emerged.
This wasn't Cyrus' first stab at "Rebel Yell": The singer first covered the 1983 single during her performance at the 2012 VH1 Divas concert:
The first night of the iHeartRadio fest also featured Drake, Sia, One Republic, Twenty One Pilots and U2, who staged their first concert of 2016 in what also marked the 40th anniversary of the Irish group; U2 formed in September 1976.
Saturday night's lineup includes Sting, Britney Spears, Ariana Grande, Tears for Fear, Cage the Elephant, Florida Georgia Line and more.