Watch a clip!
We caught up with Nathan for the series premiere.
A: What I like about Castle is that the more I play him, the more I think he's just a little misunderstood. He kind of started off as this womanizing playboy, but I think that success just comes easy to him. He's well-liked, he's very playful—even women come easy to him. It's because he's joyful in life. He's very childlike, maybe even has a bit of Peter Pan syndrome. He's never really quite grown up—I think for a lack of a male adult role model in his life. He's always surrounded by women, and he doesn't really know how to behave like a grown-up.