Armstrong is critical of monetary systems that rig the system by pegging currency values, enabling no-risk borrowing that inevitably results in collapse. The documentary views much like a spy thriller except this is real life. Considering the development of events, it is remarkable that he ever got out of prison and that the documentary was made.
The documentary is largely engrossing but covers some esoteric details of finance in a few places where it would have been helpful to have explanations and commentary by third party participants. Here are a couple of trailers and an interactive string of segments taken from the documentary with additional footage. You can skip over the German language parts.