Guest Stars Demi Lovato as Themselves Ariana Grande as Herself Nick Jonas as Himself Madonna as Herself Gwen Stefani as Herself Rihanna as Herself Britney Spears as Herself Blake Shelton as Himself Pink as Herself Céline Dion as Herself Troye Sivan as Himself Justin Bieber as Himself Meghan Trainor as Herself Tove Lo as Herself Shawn Mendes as Himself DNCE as Themselves Lukas Graham as Himself Fifth Harmony as Themselves The Go-Go's as Themselves
