Robert and Kristen: Sparks since day one!

There's no denying the chemistry between Twilight stars Robert Pattinson and Kristen Stewart. And, as Twilight director Catherine Hardwicke tells Life & Style, finding co-stars with that special spark was all part of her plan!

"[During casting] I did the whole scene in my bedroom to be sure that these two people had sparks," Hardwicke told Life & Style at the launch of Twilight: Director's Notebook in Santa Monica on March 17. "Are they intense? Are we going to believe it and love it?"

And this director didn't just stop at filming them in the bedroom; she wanted them to lock lips! "I said, 'Yes, we really want you to kiss. I want to see if this works,'" she reveals. "Because at the end of the day, if it just doesn't work, then it's not going to work for the whole movie. So I made them go ahead and kiss, and the sparks did fly!"

Will Rob and Kristen have the same passionate flame in New Moon? Pick up the latest issue of Life & Style to find out!