SANTA MONICA, Calif. -- SANTA MONICA, Calif.--Having played Hermione in the Harry Potter movies, Emma Watson was used to acting around special effects to be filled in later, but her work in the computer-animated "The Tale of Despereaux" raised such guesswork to a new level.

Playing the sad Princess Pea, who at one point is kidnapped and thrust into a "Gladiator"-like arena by some fiendish rats, the 18-year-old English actress had to concentrate all of her performance in her voice, little knowing what the final product would look like.

"Honestly, I didn't really know what to expect," she said. "I read the script. They showed me some sketches of how Pea was going to look. I saw a couple of clips. Aside from that, I didn't know where they were taking it."

Over an interview in a beach-side hotel earlier this month, Watson discussed her surprise at the finished product, her decision to stay in school, her desire to act, and, of course, her ongoing life in the world of Harry Potter.

QWhat is it about acting with just your voice that's different?