As always, no spoilers whatsoever in this review because that's just plain inconsiderate.
Saving Mr. Banks is a dual narrative portrait of the author of Mary Poppins and the creative team at Walt Disney that worked to bring it to the big screen. In one thread (1961) we have the curmudgeonly author behaving like a stark raving... well, curmudgeon as she tries to exert control over the creative process. In the other thread (1906, Australia) we unwind the story of her grim childhood that makes her a curmudgeon in the first place.
This movie has a lot of things to say not the least of which is to cast an entirely different light that beloved American classic of childhood. Mary Poppins ain't quite what you think it's about as a kid (but then what good movie IS what you think it's about when you're a kid). It's also a powerful demonstration of how our childhood influences us as adults sometimes in ways that we don't quite grasp until we look back on them from a great distance.
It's also interesting to see behind the curtain of the creative process. Avoiding spoilers, the author's primary objection is that Mary Poppins and the Banks family have become, in truth, her family over the years and sharing that vision and letting someone else have a piece of them is frightfully difficult. It does make a person wonder if all authors have this same struggle when crossing mediums.
Lastly, I'm a sucker for sentiment but this movie had the audience blowing its nose and audibly sniffing for a good hour. It's an incredibly intimate portrait. However, the kids won't think much of it and the group in the theatre with me was 50+ for the most part. All that said, highly recommended for anyone with a sentimental streak. Best movie I've seen in a month or more.
PS: The patient who sit through the credits will be treated to some photos from the movie's production and a section of the recorded conversations between the author and the production cast.