Before the original 'Transformers' came out, Megan Fox was relatively unknown. That all changed with the arrival of Michael Bay's game-changing blockbuster in '07. Now, Megan's back for more excitement in 'Transformers: Revenge of the Fallen,' in theaters and IMAX June 24, and she tells ET's own Mark Steines how her life has been changed by fame.

"I definitely feel ill-prepared; I mean, I don't know if anyone ever sits back and goes, 'Now is the moment that I think I should be a famous celebrity,'" says the Tennessee native. "I know I'm struggling with trying to figure out how to how to live in it -- but I definitely feel it's premature. I mean, I was in one movie that people have seen."

Megan's media coverage has definitely increased tenfold since the first movie, but she tries to keep it in perspective.

"I see some people who have to deal with in on an everyday basis -- I am not a Jennifer Aniston or a Britney Spears or even a Lindsay Lohan, you know?" she explains. "My pictures don't sell for that kind of money. But [of] the small level that I do deal with it, it is hard and there have been times [when] people don't want to hang out with me because they don't want to end up on the Internet. I sometimes just turn around and go back home and don't do anything and have to have someone go do my grocery shopping."

"I need to behave in a way and handle myself in a way that will cause people to take me seriously," Megan continues. "You can be sexy and be intelligent and be taken seriously, or you can be sexy and you can be out at clubs every night and not be [taken seriously]."

After a moment of reflection, she adds, "I haven't gone completely insane -- but it might happen soon."

As for 'Revenge of the Fallen,' Megan says, "Visually, it's mind blowing; twice the special effects. … I don't think I'll ever make a movie that's gonna be as financially successful as this movie is ever again."

So, what kind of role would she prefer to play next?

"Maybe, you know, something that's more of a character piece that doesn't involve a leather motorcycle outfit," she says.

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