to that mysterious married couple who went viral on vine with catchy cover songs. They've never been revealed fully on TV. But before we meet this couple live, ABC's Rachel smith has a look at their... See More
to that mysterious married couple who went viral on vine with catchy cover songs. They've never been revealed fully on TV. But before we meet this couple live, ABC's Rachel smith has a look at their story. Reporter: They are the talented twosome taking the internet by storm. ♪ Let it go let it go ♪ Reporter: Called ustheduo and use the mobile app vine to create their amazing six-second covers all while shooting their video like this. ♪ Never be the same ♪ Reporter: And, yes sh, your television is properly focused. We never see your beautiful faces. Why the mystique? What we found is that people focus more on our voices rather than our looks. Reporter: That harmony -- ♪ about the things that we could be ♪ Reporter: Has the husband and wife's vine accounts growing like weeds from 5,000 to 2 million followers in just three months. It creates conversation in the comments like who -- who are these people? Reporter: The framing technique came to the couple during a quiet night at home. Just like, Michael, I'm in my jammies. No makeup on. I'm not presentable. How about we film a vine just, you know, without showing your eyes. Reporter: Dozens of videos later the anonymous act is belling out a high note. There are times where we have to do it over again. She sings it beautifully and then, you know, I mess it up because I have an eye peeking in. Reporter: Your dreams. We want it to keep growing. We're doing what we love with the one we love. ♪ We'll never be royal ♪ Reporter: For "Good morning America," Rachel smith, ABC news, Los Angeles.
This transcript has been automatically generated and may not be 100% accurate.