This book sucks. The analysis on the happenings of the cultural revolution is mostly ahistorical and contains little to no sources. The author is clearly pushing an anti Gang of Four line and fails miserably in doing so by poor sourcing and claims. The only good thing about it is that it includes the actual transcript of the trial.
This is an important book of historical record on the Cultural Revolution - I reread it for the first time in more than 25 years and was struck by how much great detail - much of it forgotten today in discussion about that era - Bonavia mastered and presented. We've rarely seen anything like this since by China correspondents. Bonavia died too young. I would love to have seen what he would write if he were still alive today.