Angie Miller and Candice Glover's duet gets ovation, Amber Holcomb and Kree Harrison 'like superheroes' on 'American Idol'

Amber Holcomb and Kree Harrison team up to sing Adele's "Rumour Has It" next on "American Idol." Holcomb's distinctive voice really cuts through; she simply sounds like a star. Harrison is strong as well; they've got Keith Urban rocking out in his seat.

Urban praises Holcomb's "commanding stance," calls it "riveting." Nicki Minaj says "you guys are superheroes, your voices are amazing." Tells Harrision again to step it up, to challenge Holcomb like a diva would and don't let her dominate.

Angie Miller and Candice Glover then do Rihanna's "Stay." Electric from the start; a lot more back-and-forth than with the other two, they're better performers as well. Standing ovation from judges, not sure I've seen that before for a duet.

"Unbelievable!" yells Randy Jackson, "that's the way you do a duet." Calls it "incredible." Mariah Carey liked how they tailored their voices to the song.