Reporter: Hunter Hayes electrified the crowd tonight with his performance at the cma music festival. ? Your name next to mine ? Reporter: He's come a long way. Five, four, three, two, one. Reporter:... See More
Reporter: Hunter Hayes electrified the crowd tonight with his performance at the cma music festival. ? Your name next to mine ? Reporter: He's come a long way. Five, four, three, two, one. Reporter: Just a few months back, "Nightline" went on a wild ride with Hayes for a guitar-strumming, gut-busting race against the clock. Ten cities, ten concerts, in less than 24 hours, without so much as a red bull. This 22-year-old country star was trying to break the world record for the most concerts in one day. He's a prodigy who can play 30 musical instruments. And write hit songs like "I want crazy." ? I don't want easy I want crazy ? ? are you with me, baby let's be crazy ? Reporter: Hayes' debut album went platinum. And industry insiders see him as a legend in the making. This is the dream. To be here and do what we do, you know? Reporter: And as the opening act on Taylor swift's tour, he became an instant favorite among teenage girls. But he's surprisingly humble. Just being in this room period, is kind of a dream come true. Because that means we get to put on our arena tour. Reporter: Timed with the release of his second album, "Story line" Hayes put his sights on a world record, for a cause. The fact we're doing it with child hunger ends here, we get to spread the message. Reporter: We followed Hayes as he was about to embark on a tour, spanning from Boston to Philadelphia, in just 24 hours. And we were with him every step of the way. I don't know how you prepare or if you prepare for something like this. You just have to roll with the flow. Reporter: On-hand the entire time, official timekeepers from guinness. On the attempt, it is important for me to measure that hunter does play for at least 15 minutes. So, I will be at every show, ensuring that the 15 minutes are met. Reporter: It kicked off bright and early in times square, on the set of "Good morning America." Trying to break a guinness world record for most concerts in a single day. Here he is now. Reporter: Right after the "Gma" gig, Hayes and his band hopped a plane to Boston for concert number two. What's up, y'all? It's 11:30 A.M. On a school day. But there are huge crowds of young fans everywhere. Mouthing the words to each and every song. Are we ready to make some noise? Is that your first cup of coffee this whole time? Reporter: You think Hayes would be guzzling coffee or energy drinks, but he says the adrenaline of performing is his drug of choice. You look like you have so much energy. You don't look tired. Good. That's my secret goal. I wanted to say something to that effect. Reporter: Is it just an act? Are you feeling that way? No. That's how I feel, man. We get on stage, it's a natural adrenaline. Reporter: It's 10:30 P.M. And his seventh concert. And the venue is still jam-packed. How is your voice holding up? Are you feeling it, the strain? I have a lot of allergy issues. And ten cities, there's ten different climates. I have a voice. Able to hit some notes I didn't think I would hit at this point. Reporter: It's 2:30 in the morning in Asbury, New Jersey. And there's a crowd inside very excited. It's 4:30 in the morning, and hunter finishes playing concert number nine. The guinness record official has the final word. On behalf of guinness world records, we want to say congratulations, you've broken the record for most -- Reporter: You just broke the world's record. How are you feeling? Feeling good. Feeling good. Just fun. Just jam. Reporter: Finally, at the troccadero in philly, Hayes plays his last show. For "Nightline," juju Chang in Philadelphia.
This transcript has been automatically generated and may not be 100% accurate.