That's the part where I was thinking she didn't actually see the Hulk out in the cave. She was partially buried and worried about the professer. When the Hulk did show up, she was surprised, of course. David was in a cul de sac part of the cave and obscured by falling debris and dust. I guess I'll just HAVE to watch that episode to sort it all out in my mind. :oP It's been a long time since I've seen that episode. Seems as though it was later in the episode that David revealed his "condition" to her, after she got mighty curious (and had probably already figured it out) about why David was so focused on the cave drawing.