SAN DIEGO — There's plenty of mystery surrounding Len Wiseman's adaptation of "Total Recall" and much of it involves the film's two leading ladies: Kate Beckinsale and Jessica Biel. The actors play characters who are both much more than they seem at first glance — but in very different ways.

MTV News chatted with the two stars as they promoted "Total Recall" at San Diego Comic-Con, where they revealed that neither was originally intended to play the part they ended up with. Beckinsale plays Lori (Colin Farrell's onscreen wife) and Biel plays Melina, a woman who helps Farrell's Doug Quaid after he goes through the "Rekall" experience. But the casting could have gone down another way.

"I actually spoke to Len and auditioned for both," Biel recounted. "Auditioned like three different times, went in for Malina — no, I went in for Lori — then went in for Malina and then went back. Crazy.

"Actually, [I] read with Colin for Lori, wild enough, and then Len and I just talked about it," she continued. "I sat by myself for a while and thought, 'You know what? I want to be the heartbeat of this movie. I want to be that person who's with Colin, going through it, getting involved in it."

After some more reflection, Biel concluded that the part of Malina would allow her to stretch in ways she hadn't yet onscreen.

"I felt like I had done a little bit of going after the heroines in 'A-Team.' I was sort of with them but also kind of going after them, and I wanted to experience more of the emotional connection of the character and of the film, and he agreed," Biel explained. "[Wiseman] goes, 'And I think Kate would be amazing as Lori because she doesn't really do that kind of a thing. She's usually the heroine.' So it was a perfect slot. We just fit in perfectly."

Apparently, Beckinsale had a scheduling conflict and almost wasn't in the movie at all. But since Wiseman is her frequent collaborator (and happens to be her husband), he worked to ensure that she was involved in the project.

"I know when my husband first signed on to the project, he was like, 'Oh my god, I really want you to play this bitch-psycho wife.' I was totally offended and didn't think any more of it for a while," Beckinsale admitted. "I suddenly got a call, not from my husband, but from the head of Sony saying, 'Will you play Lori?' I thought it was a joke because I thought at least my husband was going to give me a heads-up ... so that was wild."

In fact, Wiseman actually had a rather different role in mind for Beckinsale. "We'd had a conversation about the fact that I wasn't available and we were both being very grown-up about it and he said, 'Well, maybe, will you play the three-breasted hooker just so that you're in the movie?' And I was like, 'OK,' because it had been a very long time since I saw the movie ['Total Recall']," she said.

"I'm so glad that I didn't do that. I mean, she gets more attention than Jessica or me put together," Beckinsale laughed. "My daughter would die. She'd be so mad at me, going into eighth grade, if I was walking around with three boobs all the time. She'd be really annoyed."

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