View the Gallery / 51 Photos »

Actress Jessica Biel, sans boyfriend Justin Timberlake, hit the red carpet with co-star Dwayne Johnson for the premiere of their animated sci-fi adventure film Planet 51.

The film is about American astronaut Captain Charles “Chuck” Baker [Johnson] lands on Planet 51 thinking he’s the first person to step foot on it. To his surprise, he finds that this planet is inhabited by little green people who are happily living in a white picket fence world, and whose only fear is that it will be overrun by alien invaders…like Chuck!

As for starring in the animated film Dwayne said, “For me it was the first time I had done animation and had to try to bring a character to life with my voice — just with pitch.”

Biel had a few struggles with her voice. She had to work on the pitch of her voice to make Neela sound less adult. “They wanted it higher. I was going … ” (pouring on the come-hither huskiness) … ” ‘Yeah well.’ And they were like, ‘We’re not trying to make THAT movie,’ ” she says, laughing.

“I was more like up here, in this pitch, which was hard for me at first, because I want to be … ” (lowering her voice again) … “down here.”

I just want to see the movie along to hear what Jessica ended up sounding like.

Gallery Info: Jessica Biel, Dwayne Johnson, Boo Boo Stewart, Dylan McDermott, Justin Chambers, Stephanie Pratt and Kayla Ewell at the Los Angeles premiere of Planet 51.