I won't repeat the plot as many other comments have taken care of that. Many of Robin Williams' performances have been Robin Williams playing a character -- there's a wink and a hint that he'll bust out with some shtick at any time. He (or the director, or both) contain that impulse to an impressive degree in this movie and do so without the excessive sincerity that Williams often substitutes for emotion in his other parts. (Good Will Hunting contains an overrated performance of this type.) Example: in the scene where he takes on the voices of Churchill, Stalin, and others, it's wholly within his character's desire to persuade the little girl (who's wonderfully played, by the way) that hope remains. I agree that some of the actors, notably Alan Arkin, aren't very good, but other, less-well-known ones support the movie well. In addition, I thought the production design, cinematography, and editing were thoughtful and well-done. And I liked the ending...