This is a historical docudrama with a mixture of academic talking heads and recreated drama scenes and part documentary.
This kind of thing is a tough genre to pull off and I do not think it succeeds here. The programme tries to recreate the 1605 Gunpowder Plot from the men on the inside with Guy Fawkes's attempt to blow up Parliament being just a first step to arouse rebellion among Catholics in England.
The story unfolds through the interrogation of one of the key plotter's, Thomas Winter as we see through him how the conspiracy came together and ultimately failed.
The talking heads of experts make out that we are getting more facts and less conjecture, the dramatic scenes add some interest but it was still a mixture of things I already knew with some dramatic licence and hypothesis despite the presence of academics.