Four Days in November sets out to put some "flesh" on the dry bones of the Warren Commission Report, and also attempts to make it more "believable" to people who still have reservations as to its explaination of the events in Dallas, by anticipating readers' questions and debunking silly conspiracy arguments. Just beware, remember that Bugliosi's background, however, is in the prosecution business and his book, extremely well written, and a much enjoyable read as it is, is just that: prosecutor's evidence, setting up to prove that Oswald's did it, on his own, etc. I found the Jack Ruby section, where Bugliosi is at pains to describe how his shooting of Oswald was the result of a "spur of the moment" decision very laborious and somehow unconvincing. I see this book as the anti-thesis of Mark Lane's early book "Rush to Judgement" which set out to prove Oswald's innocence. I don't think one will be more advanced on either view after reading Four Days in November, but it is recommended read in asmuch as Bugliosi knows how to keep the reader's attention.