This question already has an answer here:
I'm looking to be introduced to interesting documentaries in the field of design, I saw Helvetica and it blew my mind and am looking for films similar to this one.
This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.
Whoa! Major subject! I think the simplest answer would be the
On that page, you can go through a massive backlog of previous films, filmmakers and subjects.
...or you could search youtube for "design film"....