A documentary about the secret ruler of Studio Ghibli: Ushiko the cat... If I had to guess I'd say she had about the same amount of screentime as Takahata.
So despite the three men being on the poster, most of the time is spent with Miyazaki. I was a bit reluctant at the beginning because as a documentary I would't say it's structure is commendable but it works as a document of Miyazaki work process and his thoughts during the production of his now last movie "The Wind Rises". You get a really good insight of the slightly eccentric man and his relationship with Suzuki and Takahata with a lot of background information to the movie given that it is a more personal work.
If you like Studio Ghibli's works and are interested in the men behind it I can only recommend it but for a casual watcher to just jump in I don't think it does the best job. Oh, and be wary: the ending(s) get spoilt for "The Wind Rises" so you might want to watch the movie first.