The person in question in this documentary is named Nick Yarris, and he does almost all of the commentary throughout the entire 96 minutes.

source
This guy Nick, is so compelling and entertaining, that i was convinced that while he was talking that Nick Yarris wasn't actually a real person. I was convinced that Nick was a fictional being or at the least there was an actor playing his role.
There are no actors, there is no fiction (unless he is lying) and this is a truly compelling story of a many wrongfully imprisoned for a long period of time.

source
Most of this movie is simply a one-on-one conversation with Nick himslef and not a great deal else. However, Nick is so incredibly passionate in his retelling of the events that took pace over the past 2 decades.... honestly, the film doesn't need more than that.
I was really moved by his performance and after spending 20 years in prison for a crime he did not commit i think that Nick really did an absolutely top-shelf job showing genuine emotion to the BBC during their filming of this doco. I don't want to give too many spoilers but the basic premise of this film was this:
I watch a lot of documentaries and this is likely the most compelling one I have seen in a while. I think the major reason for my feeling that way is because i too would feel bored by the fact that I am primarily dealing with looking at one person while he tells a story for an hour an a half, but man... oh man did this guy Nick tell the story properly..... This dude needed no assistance.
I encourage a lot of people to watch a lot of things on fast-forward. This is not one of those things. There is no filler... there is no fluff.... every word this man says is filled with the passion that only a person who has been in a cage for many years can come up with...... and come up with it Nick certainly did.

very few people deserve this stamp, but Nick does