They are the talented twosome taking the Internet by storm.

Calling themselves "Us the Duo," Carissa and Michael Alvarado use the popular app Vine to post amazing six-second covers of hit songs. But there is a catch. The videos show only a partial view of their faces while they sing.

That is, until now.

The husband-and-wife duo revealed the faces behind their angelic voices for the first time on "Good Morning America" today, singing a medley of their hottest Vine hits.

"It's crazy," Carissa Alvarado explained of their new found fame on "GMA." "We didn't expect it at all. We just wanted to promote our album and it just took off."

The mysterious, faceless element of the unknown has certainly proved effective for the singing sensations, as their harmonies alone have shot their Vine account to incredible success.

"What we found by doing that was people focus more on our voices than on our looks," Michael Alvarado said.

Since they started posting their videos in December, the couple went from 5,000 to 2 million followers, all while covering songs by singers including Katy Perry, Selena Gomez, Imagine Dragons and Lauryn Hill.

Their unusual framing technique developed during a quiet night in their home.

"We were going to film one night and we were trying to make a Vine cause we had an album out and we were like 'we need to market this album soon.' So we thought let's make a Vine, we've never made a Vine before, and she looks at me and she's like, 'Michael, I'm in my jammies,'" he said.

"I have no makeup on, I'm not presentable. I look crazy without it," she added, recalling the experience.

Carissa was eating popcorn, and Michael said he was in "chill mode."

"I was like 'okay, okay, let's meet halfway. This is marriage, let's compromise,'" he said. "How about we film a Vine without showing your eyes?' She gladly agreed. And we made our first singing Vine together and it came out very nice."

They want to keep on making music together.

"We are doing what we love with the one that we love," she said. "So it's been a fun journey."