Isabel Lucas vs. Megan Fox: Who is Hotter?

Action-packed scenes and fighting robots weren't the only things to get audience heart's pumping when "Transformers" hit theatres back in 2007. A performance by actress Megan Fox also turned up the heat.

Playing the car-savvy love interest of Sam Witwicky, Shia LaBeouf, the 23-year-old bombshell left a lasting impression, but this time around she has some serious competition. Australian actress Isabel Lucas joins the cast for "Transformers: Revenge of the Fallen" as Sam's new college classmate.

Lucas landed the role through a recommendation of Steven Spielberg, who she worked with on the set of his HBO miniseries "The Pacific," reported New York Daily News.

"I'm still pinching myself that's how it came about," she said.

As far as sharing the hottie spotlight goes, the 24-year-old says there haven't been any catfights.

"Megan was really sisterly and warm to me when I began working on the production. She was aware that it is intimidating coming onto a new set where everyone is established, and she was cool," she said.

Besides their looks, the two beauties have one other thing in common; there's rumors of romantic involvement with co-star Shia LaBeouf.

"There is a bond, but he also can be a brat and we have fistfights and brawl. He's like a brother," Fox said.