A film was already produced, nearly 30 years ago. It is called: "Witnesses of Jehovah" by Jeremiah Films.
I came across this gem back in 2005. I was floored. Mainly, because it packed all of the major flaws of that time (that are actually still relevant today) into an hour that felt like a one-two punch to the gut. I was actually physically ill after viewing it. To be smacked with so much information in one spot, in such a short period of time actually caused me illness. I showed it to my mother. She wished she had seen it in 1986, it might have helped her exit sooner. What is really interesting, is to watch this documentary today with the perspective of time passed. They talk about 1914 and how it has to change, just as previous doctrines before my time changed. That part is really gut-wrenching.
Here it is, Enjoy!
<iframe width="420" height="315" src="https://www.youtube.com/embed/VE3zp9FiyiQ" frameborder="0" allowfullscreen></iframe>