LOS ANGELES — At the risk of bringing you down, there's a good chance that a 12-year-old girl is gonna have a better 2010 than any of us.

Her name is Chloe Moretz, better known as Joseph Gordon-Levitt's precocious little sister in "(500) Days of Summer." This year she'll not only enter her teens, but release three diverse, highly anticipated movies: The superhero action film "Kick-Ass," the kid-friendly adaptation of the best-selling "Diary of a Wimpy Kid" series, and the vampire-in-love drama "Let Me In."

On the big screen, she's about to break out as a badass assassin. In real life, her bedtime is 9:30 and she has to refer to the movie as "Kick-Butt" around her parents. Recently, Chloe stopped by the MTV studios to discuss her inclusion in our "10 to Watch in 2010" series, as well as where Hollywood ends and middle school begins.

MTV: So Chloe, congratulations! You are one of our 10 people to watch in 2010!

Chloe Moretz: I know; thank you so much.

MTV: We'll be watching you.

Moretz: [Laughs.] That's kinda creepy!

MTV: Now, at this point you're 12 years old, soon to be 13. Most of us know you from "(500) Days of Summer," but they recently began showing "Kick-Ass" to some advance audiences, and the buzz seems to be that it's "Citizen Kane" meets "The Dark Knight."

Moretz: That's a huge compliment. I'm just so shocked by all of this and how amazing it is. We just released all the commercials for it, and there's so much buzz about it and people are loving it. It's so exciting, because I really put my heart and soul into that movie.

MTV: Give us the film's plot, in your own words.

Moretz: Basically, Aaron Johnson plays Kick-Ass. He's a regular, everyday kid — a nerdy comic book fan. He's like, "Why doesn't anyone ever try to be Batman? Just a normal guy turned hero?" So he goes out, tries, and gets totally beaten up; he gets stabbed, and then run over by a car. He gets all this [prosthetic] metal put into his back so he can walk, otherwise he'd be totally paralyzed. And that becomes almost like a human shield on his back, so if you hit him he won't feel it. So, he goes out and [tries to be a hero] again and succeeds. That's when [Hit-Girl] and Big Daddy come in.

MTV: And you're Hit-Girl, a badass little-girl superhero.

Moretz: Yes, and Big Daddy is played by Nicolas Cage. We show up at his house, say, "We know about you," and he realizes we're real vigilantes. I've been trained since I was a baby to be this crazy assassin girl. What I like about the character is that she's an assassin, but at the same time she is still just an 11-year-old girl. She doesn't know any better; it's just how she was raised.

MTV: And none of these heroes have superpowers?

Moretz: No, just guns and knives and stuff.

MTV: Tell us about your favorite scene in the movie.

Moretz: When I go [to] kill a drug lord to get back at him — I think I kill 30 guys in, like, 30 seconds, in one corridor with two guns. Then I run out [of bullets], pick up another gun and shoot it, throw it at them, jump over a table and throw my legs forward, kicking [a bad guy] ... later, I get stuck in a cupboard and have to throw kitchen knives. It's so fun; it was the coolest thing ever.

MTV: And how much of this training is useful in real life? If you were in a Starbucks with your parents and somebody tried to hold it up, could you kick that guy's ass?

Moretz: I'd be terrified. [Laughs.] I'd probably cry, scream and be like, "Call 911! I don't want to die!"

MTV: But after this movie, everyone's gonna think you're a badass!

Moretz: They'll think it — but if I wrestle my dad, he can take me down in two seconds with just his fingers. I'm a complete scaredy-cat.

MTV: The film supposedly sets up a sequel. Would you like to come back as Hit-Girl?

Moretz: I would love to. I can't say anything about [the ending], but I would love to be Hit-Girl twice, three times, four times in my life.

MTV: Tell us about April's "Diary of a Wimpy Kid." We know the books are very popular — what's the movie about?

Moretz: The wimpy kid is a nerd, he's the total outcast of school. I'm an avant-garde school-paper editor with these crazy hairstyles and funky, out-of-nowhere clothes. It's a fun role for me to do. The wimpy kid goes from elementary school to middle school, and he's trying to survive in middle school. I'm in middle school now — it's really tough, the transition from little school to teenager ... he's trying to get a popular kid reputation ... it's a mixture, I think, of the first two books.

MTV: You also have "Let Me In" coming out in October, a remake of "Let the Right One In." Tell us about that film.

Moretz: It's about a boy who lives in Los Alamos, New Mexico. Growing up, not many people like him, he's not popular. He's wimpy, kind of an outcast. Then this girl moves in, she's totally different. She doesn't wear shoes, wears raggedy clothes — it's sort of like "Romeo and Juliet" with vampires. She can't be with him, because she's a vampire. But they fall in love; it's a really sweet coming-of-age story between a little boy and a little girl.

MTV: With "Twilight" and "True Blood" and "The Vampire Diaries" and everything else, bloodsuckers-in-love are very popular. What will make your film stand out?

Moretz: [Our vampires] aren't very glamorous. It's a very sad and heavy burden to have; it's not easy to live. You need blood to live, and that's not an easy thing to go through. [My character, Abby] has to kill for it. She's a very sweet, loving person. And that's why I relate to the character — she's a beast, it's a demon inside of her and she can't stop it from coming out ... when I turn into a vampire, it's terrifying.

MTV: "Let Me In" has gore and violence. "Kick-Ass" has lots of adult language, and you kill dozens of people. As a 12-year-old girl, how do you deal with these themes at work, yet stay normal at home?

Moretz: It's a movie; it's not me. If I ever uttered one word that I said in ["Kick-Ass"], I would be grounded for years! I'd be stuck in my room until I was 20! I would never in a million years say that. I'm an average, everyday girl; when I act with my friends, I'm totally immature ... I have to go to bed at 9:30, if I'm up late on the computer, I lose it for two months.

MTV: Don't you ever want to say, "Mom, you can't take away my computer! I'm a movie star!"

Moretz: [Laughs.] If I ever said that, my brothers would totally kill me. I have four brothers — and with my mom and my dad, they keep me totally grounded. My mom has always said that if I get a big head, she'll take me out of this business as quickly as I got into it.

MTV: We'll hold you to that as we interview you over the years, so make sure your head is still normal-sized after you win the Oscar.

Moretz: Yes, thank you. [Laughs.] Keep me in check.

Check out everything we've got on "Kick-Ass."

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