Many if not all the stories in this book have been published elsewhere before but that alone does not make them true. Nelson made this book interesting because he weaved the stories together in a form that is captivating. He keeps them short and pacy. He implicates Johnson in the stories by constantly weaving his own opinion and inferences into them, e.g. "Meanwhile, as Johnson was manipulating and sabotaging the president he had sworn to support, John Kennedy thought that he had neutralized Johnson by putting him into the vice presidency".
Nelson shows that LBJ was one man who had the motives to have JFK killed. He shows (by his own inferences and conclusions) that LBJ was a nasty, wicked, and ambitious man who was extremely close to the FBI director, J Edgar Hooover. From that angle, Nelson also pointed out all the (old) stories about the dirt that Hoover had on Kennedy and how Hoover helped Johnson in many ways, from compelling Kennedy to name him his vice presidential candidate to suppressing evidence concerning the assasination.
What is, and has always been, controversial, was the belief that Lee Harvey Oswald was a lone gunman. Nelson rethreads all the dubious evidence and investigation procedures to show that Oswald was one small cog in the assasination masterminded by LBJ. Nelson criticizes the Warren Commission for discarding or ignoring vital evidence, eg the secretary who saw Oswald in the same building Oswald was stopped by a police officer shortly after the killing. Why this was so critical was not explained. We might infer that Oswald was not the gunman. That leads to the crux of the flaw in this book. Oswald might not be the real killer, he might have been one of several killers, there might have been a conspiracy by various people to kill Kennedy, but Nelson has not shown any evidence that LBJ was the mastermind behind it. He merely shows that LBJ had the reasons, the meanness, and the closeness to do it, and therefore, because no evidence connected him to the assasination, he must have been the mastermind. So, although the book was interesting to read, the title is misleading and the assumptions in the book are a little suspect. It may be interesting for readers with the curiosity, time, and energy, to read and compare the first edition of this book which was published in 2010 and completely withdrawn from sale in the first part of 2011. The second edition was published by a different publisher, "professionally redone", according to Nelson.