Underwood Reveals Grammys Performance Secret

The Grammys delivered another set of electrifying performances on Sunday night, from new artists like fun. to longtime rapper and the show's host LL Cool J. Among the night's performers was country sensation Carrie Underwood, who revealed a secret to ET backstage about her fascinating light-show performance.

As Underwood began singing her song "Two Black Cadillacs" after performing "Blown Away," the country music star's dress began to illuminate with an intricate lighted design, transforming her dress into a projector screen.

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It was apparent that she was unable to move while the performance was occurring so that she wouldn't disturb the alignment between her dress and the video projector, but Underwood explains why she may have seemed a few inches taller on the Grammys stage.

"It was all projection and it took a lot of people getting everything just right so the projection wasn't [off]," said Underwood, who revealed that the dress was made special for the occasion. "I had to stand in the exact same place. I was actually barefoot on apple boxes."

Although she's been a star performer since winning American Idol in 2005, Underwood has never quite found an occasion for which to sing barefoot onstage until Sunday night.

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"I never sing barefoot and it felt really weird," she said, "...but they were nice enough to put those little Dr. Scholl's [insoles] underneath my feet so it...felt good, kind of cool."

In addition to singing barefoot on apple boxes, Underwood won her sixth Grammy at the ceremony, her fourth Best Female Country Performance award for "Blown Away." Despite winning six Grammys in six years, she remains humbled by the awards.

"It's wonderful. I'm just so happy to be here and can't believe that I have another one to add to my collection," said Underwood, who released her fourth studio album, Blown Away, last May. "...It's always a surprise and it's always wonderful."

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