"Greek" and "Summerland" teen heartthrob Jesse McCartney returns to his music roots after a two-year absence with a new video, "Shake," and a new CD, Have It All. But he is also fulfilling a childhood dream by voicing cartoon characters.

Now ET talks to the singer/actor about his sexy new video and his upcoming action-hero animated series, "Young Justice," which will air on the Cartoon Network.

ETonline: The theme of "Young Justice" seems to be proving yourself over and over again. Is that something that happens in your real life?

Jesse McCartney: Proving yourself over and over again, certainly that is the case with Robin and Dick Grayson. He is a young, prepubescent superhero, who needs to prove himself as the leader of this team. In the beginning of the season, you see he is this young, cocky teen who isn't ready to head a team like this yet. With the help of Batman, he eventually grows up a little bit and becomes a young man. You can see that he is a natural born leader. He has all these lives in his hand.

With me, I wouldn't say it is that in depth. I wouldn't say that I have that many lives to save. But I would say with my music career, I have certainly had to prove myself over the years to stick around this long. I owe a lot of it to the fans. If you listen to the album that is coming out this month, and then you listen to my first album, I think you will hear a lot of change and evolution. That is part of the process when you want to have longevity.

ETonline: From that album, you have a new video, "Shake," coming out. What is the story with that?

Jesse McCartney: The video just came out three days ago. It is pretty viral right now. It is all over the place. It just premiered on a network. All the fans are giving me their reactions. For the most part, it is all positive. It is a bit racier … definitely, one of the sexier videos I have done in awhile. I think it was a good image to have out there after two years, or however long it has been since I have been on the radio.

ETonline: Are you a fan of comics?

Jesse McCartney: Not in the sense that I bought every comic. I was more of an action-hero fan. I went to every movie, watched every show when I was a kid -- Superman, Batman -- I had the lunchbox. I was full-in. I was obsessed with animation as a child and was inspired at an early age to want to learn different voices. When I was a kid, I wanted to emulate Mel Blanc, who is arguably one of the most legendary voiceover recording artist of our time. I used to watch all the cartoons where he would voice Daffy, Elmer Fudd and Porky the Pig. I knew one day I wanted to do that. I am living a childhood dream by doing shows like "Young Justice."

ETonline: I notice you are doing a lot of voiceover work. What is the appeal of that as opposed to appearing onscreen?

Jesse McCartney: For one, you are not appearing onscreen, so you can roll up to the session in whatever you are wearing: my pajamas or whatever I had on the night before. It is also a way to express yourself with just your vocal chords. You can't use your face. They are animating it. You really have one tool and that is your voice. If you dive in and dig in, you would be surprised what you can do with just your vocal chords. I am the youngest guy in the studio and I have been doing it for five or six years.

ETonline: You started acting young. Which actors that started their careers young and are still acting do you emulate?

Jesse McCartney: My biggest hero when I was a kid was Will Smith. I used to watch "Fresh Prince" and I was a huge fan of his albums. I bought all of his albums when I was a kid. Now, he is the biggest movie star in the world. Mark Wahlberg and Leonardo DiCaprio are two young actors … 'The Basketball Diaries' was a childhood favorite of mine.

ETonline: How do you steer clear of the pitfalls other young stars go through?

Jesse McCartney: I wouldn't say there is zero negative press. Anybody who has a career is going to have to deal with a rumor in their time, or something that usually isn't true. I have a great team behind me and a family that supports me. I just care too much about my career. I have been working too long to let it slip away for something stupid. Having a career in this industry, once you get it, you have to hold on because it can so easily be taken away from you. I think if you know that, I think you will be alright.

ETonline: How did you know at such a young age that this is what you wanted to do?

Jesse McCartney: When I was 7 years old, I did a community production of Oliver, the show. My entire family was in the show with me. My parents were musically inclined. They were singer/songwriters in the '70s, so I grew up in a musical household. I think I knew so early on because I got a reaction when I was seven. I played Oliver. I remember when I came out to take a bow, everybody cheering and clapping. I thought, "Wow! That is a really cool feeling and I want to feel that again." For the next three years, I did three classic productions at this theater until I was nine or 10. Someone said, "You should take him down to the city and see if he can do it professionally." My mother did and the rest is history.

ETonline: You mentioned that "Shake" is a little sexier than the videos you have done before. Is that because you started so young that you are trying to change your image to play more sophisticated roles?

Jesse McCartney: I think it is just because I have gotten older and more sophisticated. That just naturally comes out. I am 23 now. I will be 24 very soon. People don't know how old I am. They are so used to having a 16-year-old kid in front of them. I am still learning, but I have learned a lot over that time. I think it is coming out in the music and the imaging. I think it is important to grow. Your fans are growing up with you whether you like it or not. You have to keep it fresh and exciting for them. You have to bring something new to the table each time.

"Young Justice" premieres with a special one-hour movie event on Friday, November 26 at 7 p.m. on the Cartoon Network. Jesse's Have It All CD will drop on December 28.

"Young Justice" © Warner Bros. Entertainment Inc. "Young Justice" and all related characters and elements are trademarks of and © DC Comics.

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