It is always fascinating to see the innards of the making of a movie. People that are working so much before you even know that the idea exists. Superman Lives, though, was not that special an idea.
It would have been fun to see a long hared Nicolas Cage play Superman (and I honestly mean it, especially since he was still young and caring enough about his roles) and Tim Burton would have probably reinvented the superhero genre all by his lonesome. However it would have been neither completely revolutionary nor conservatory enough to appeal to movie studios. Its cancellation was not possible, but the most probable outcome.
The documentary goes ahead and describes how the work for the movie started and how they prepared concepts and costumes and they were weeks from starting filming when the project was canceled. Fun to see Kevin Smith contradict Jon Peters on how things actually happened and who had which idea, but in the end the viewer doesn't care one way or the other.
I feel that the documentary, unlike others in the genre, like Jodorowsky's Dune, failed completely in making the viewer care. You didn't see Cage heartbroken for not making the film (in fact he didn't appear at all, except in archive footage), you didn't see Smith or Peters cry tears of frustration for not getting the thing done, and the footage about their preparations and the minute details about the Superman costume left me cold.
Bottom line: Good to watch it in order to learn how movies get conceived and made. Bad if you want to enjoy yourself or feel anything about this movie that was not made.
