Luna is brave, kind, funny, unique and so many other things, one of which is smart. Luna is different from most characters that you meet in books. There is always that quirky character who everyone loves because they're so different and funny. Well, Luna is that character in the Harry Potter series. Except for one thing, she's also extremely wise, "Being different isn't a bad thing. It means you're brave enough to be yourself." -Luna Lovegood. Luna is probably one of the smartest characters in the books and movies. She is the only one who still believes in the Diadem of Ravenclaw, which saved the wizarding world. If Luna hadn't known the Grey Lady, then Harry wouldn't have known where to find the Diadem, therefore leaving Voldemort with one last Horcrux and then it would all have started over again.