Certainly the cast is excellent, but while plauding them don't forget that no-one on screen is making it up. They wouldn't be telling this awful, true story if they didn't have a script. Full marks to screenwriter Gwyneth Hughes for condensing 20+ years of many individual tales and mind-boggling bureaucratic complexity into four hours of compelling drama.
(PS. Full marks too for magazine Private Eye, that has followed this travesty for years and years - and shame on all the mainstream press who avoided it.)