An hour long documentary on north Korea recently published on YouTube. Some interesting footage and analysis.
I was interviewed for this documentary about a year ago and it also includes others such as Dr. Victor Cha, Kieth Luse, and Ambassador Joe DeTrani.
This was produced by a European documentary team (based in France). It covers a lot of ground from Kim Jong-un's schooling to Jang Sang Taek's execution and much more.
I am not sure where the idea that Kim Jong-un is grooming his sister for succession came from.