'The Hunger Games' ' Jennifer Lawrence Compares Katniss to 'Alien' 's Ripley

Sigourney Weaver's character has the same "fighting spirit," she says

Photo: Steve Granitz/WireImage

As the official leading lady of The Hunger Games, Jennifer Lawrence knows she’s landed an out-of-this-world role – in more ways than one.

Taking on the part of Katniss Everdeen, a fierce and feisty heroine competing in the ultimate game of life-or-death, Lawrence, 20, has extra special, extraterrestrial inspiration for tapping into the “fighting spirit” of her character.

“Sigourney Weaver’s Ripley in Alien is the first [movie] that comes to mind,” she tells Entertainment Weekly of an older yet similarly famous heroine.

And while she may not be kicking alien-butt in the adaptation of Suzanne Collins’s beloved trilogy, Lawrence knows one thing: There’s a lot of fans that will want to kick her butt if she doesn’t deliver.

“I have a huge responsibility to the fans of this incredible book, and I don’t take it lightly,” she said Friday. “I will give everything I have to these movies and to this role to make it worthy of Suzanne Collins’s masterpiece.”

But for fans of the book that are skeptical – perhaps about Lawrence’s older age or head of blonde hair – Director Gary Ross tells EW the choice was “the easiest casting decision I ever made in my life … She came in and read for me, and it just knocked me out.” Plus, he says, “we can easily deal with Jennifer’s hair color.”