Only ET sat down with the Maroon 5 frontman ahead of the band's big performance.
Aguilera and Lovato collaborated on the single 'Fall in Line,' which is currently nominated for a GRAMMY.
The rapper adds a new flavor to the Backstreet Boys classic, 'I Want It That Way.'
The 16-show residency will kick off on May 31 and continue with performances in June, September and October.
The GRAMMY-winning artist also reveals which singers she's going to for advice.
'Christina Aguilera: The Xperience' launches May 31 at the Zappos Theater inside the Planet Hollywood Resort & Casino in Las Vegas.
"He’s like, ‘Dude, your album. I listened to it the entire season.’"
The pop icon is making her way to Sin City.
The former Disney star enjoys busting a move to the 2004 pop song.
The salsa singer was blown away by the tiny dancer's moves.
The rapper also claimed he slept with 'three Kardashians' in his 2016 track, 'Sauce.'
The 'RuPaul's Drag Race All Stars' queen reveals an in-depth look at the making of her first music video.
The boy band's tenth studio album, 'DNA,' is now available.
The pop-rap duo stopped by the ET Studio for a special performance off their new album, 'A Good Friend Is Nice,' available Jan. 25.
