I think it may be from the description of episode nine of the Rise of the Nazi party documentary (my emphasis):

With the Red Army closing in on Berlin, Hitler is a wreck of a man: prematurely aged, pill-dependent, losing touch with reality, and determined to fight to the end.

I suspect the "documentary" word matches the overall description of the series (again my emphasis):

This 10-episode documentary chronicles how Hitler and his inner circle rose to power by exploiting the economic turmoil of their time.