Joe Mazzello Joe Mazzello

As HBO viewers begin drinking in the second half of The Pacific this weekend, they'll see the story line of Marine Eugene B. Sledge really kick in — which means they'll be seeing a lot more of Joe Mazzello.

Just like co-star James Badge Dale, Mazzello made sure he read his character's memoir (1981's With the Old Breed) and met his widow and children.

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The book was particularly helpful to prepare for a scene in which someone close to Sledge dies. Mazzello read the passage about that on-set, recalling: "I really felt like I was getting directions from the man himself. Eugene was speaking to me and telling me how he felt, and I just tried to use what he gave me and put that on-screen.

"And then also talking to his two sons — I felt like I was talking to Eugene; they had his same characteristics and attitudes and humor and beliefs, and I really felt like when I spoke to them that I was actually getting to converse with the man that I'll never be able to meet."

What struck him most about the book was that Sledge recounted "these brutal things that happened to him with total bluntness, like it's a grocery list," Mazzello says.

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"I remember having to put the book down sometimes because what he would say would just be so unbearable to think of going through, and he would say it just like it was his normal job," Mazzello says. "There was no flashiness at times. But then once he describes all of that, he would then editorialize and talk about how he felt about it inside."

Movie fans may well remember Mazzello from his child acting days in such features as Radio Flyer, Jurassic Park, The River Wild and Simon Birch. He's still recognized from his early work and gets comments like, "Hey, I grew up with you."

Now that the 26-year-old actor has gone from dodging velociraptors to fighting the Japanese, he's waiting to see what kind of attention and acting possibilities come his way. Of course, he acknowledges, most of his work remains to be seen in upcoming Episodes 6 through 10, the first of which features Sledge and the other Marines fighting in Peleliu while Sledge's parents worry about him back in Alabama.

"It's kind of, right now, in that limbo period: People knowing about it, very interested in me, but waiting to see what I can do," Mazzello says.

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Mazzello managed to avoid the classic pitfalls of child stardom, though he jokes that he didn't. "I was in jail for seven years. Sold heroin — no," he says, stopping to laugh.

"You know what? It was my parents. I grew up in upstate New York, and that's where I stayed. I never moved out to Hollywood and got, like, totally engrossed in that scene. In fact, I think that scene is very, very dangerous for kids. For me, I had two lives. I would go and have these great experiences in these exotic locations and have so much fun and love every minute of it. But then I would go home and I would be a normal kid. I went to a Catholic school. I would play in the leaves and play kickball with my friends, and have snow days and just felt like my life was totally normal. So I think it was that balance. The acting thing never consumed me."

Whether or not The Pacific leads to more parts for Mazzello, he's already finished a role in an unauthorized biopic about the Facebook founders titled The Social Network, slated for a fall release. (Starring Jesse Eisenberg and Justin Timberlake, the film is directed by David Fincher and written by Aaron Sorkin.)

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And there's always other work in the industry. Mazzello went to the University of Southern California to learn how to function behind the camera rather than in front of it. "I want to be an actor first and foremost, but I also would love to keep up my directing chops and writing and stuff like that. I just really want to make movies any way I can," Mazzello says.

He's also finished writing a script with his girlfriend, adding: "I'm just trying to put as many balls in the air as I can."

The Pacific airs Sundays at 9/8c on HBO.