Portraying the junior James Bond means, Muniz says, he had a great time playing with all the gadgets.
He tells The Early Show co-anchor Hannah Storm, "It's awesome. That's part of the fun with the spy movies, getting to see the cool gadgets that they get to use."
Being the accomplished undercover spy is every teenager's dream, Muniz says. Besides the gadgets, he says he got to do 95 of the stunts.
He notes, "Why do an action movie if you're not going to do the action? I wanted to do every bit I could, you know, because I hate when they show the actor, like, pretend to start doing, like, a kick or something and they do a wide shot with a stunt double. Then they cut back."
To prepare for the physicality of his role he trained rigorously and with great enthusiasm. He says, "That was cool because I wanted to be able to do every fighting thing as possible. During the first (film), I did most of the fighting, but there were a few things here and there I couldn't do. I wanted to be sure I could get those kicks and get those moves down before we did the second one. I did about four hours of training every day, two hours of lifting, two hours of martial arts."
Also in the film is Anthony Anderson, playing CIA reject Derek. Anderson was specially brought into the film to add comedy, an element, Muniz points out, the first movie lacked.
"He's definitely comic and he brought in so much," Muniz says, "We didn't know each other but met a few times. We were excited when I found out he was going to do the movie and we were going to work together because he's absolutely hilarious. We had such a great time on the set. He's non-stop cracking up jokes. I don't think one word that he said in the movie was actually scripted. It was ad-lib."
Next for Muniz, who is now 18, is a search for more adult roles.
"I'm at a critical point where I have to make the transition from child to adult actor or child to respectable actor and I'm really trying to do that," he says. "It's tough. I always thought that I would turn 18 and continue to do what I was doing and be an adult actor, but it's more than that: pick the right roles and work with the right people and get involved in the right stuff and hope everything will work out."
One thing he is certain, he still wants to be called Frankie.
"Frank just sounds way too old to me," he says.