For "American Idol's" Feb. 11 episode, the first group of semi-finalists were each paired with a former "Idol" finalist -- and some of the pairings produced beautiful music together.

Case in point, Sonika Vaid singing Adele's "Skyfall" with Season 13 winner Caleb Johnson. It might seem like an unusual pairing -- as Vaid says, "At first I was like, 'Oh my god, he's so rock!'" -- but it ended up being an incredible duet.

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The judges praised Vaid for being able to hold her own against such a powerful voice like Johnson's.

"I think you're just an incredible singer and standing up there with a guy who sings that high and that loud is hard to do, you really held your own with it," says Harry Connick Jr.

Keith Urban adds, "I loved hearing Caleb sing again, it was terrific. That was a great song for you guys. You actually were really great together. I would have loved that from you regardless, so if I separate you from Caleb, that was a really great performance, Sonika."

Posted by:Andrea Reiher

TV critic by way of law school, Andrea Reiher enjoys everything from highbrow drama to clever comedy to the best reality TV has to offer. Her TV heroes include CJ Cregg, Spencer Hastings, Diane Lockhart, Juliet O'Hara and Buffy Summers. TV words to live by: "I'm a slayer, ask me how."