When I was at University back in 1988, I first heard that there was an alternative to the official story that Lee Harvey Oswald shot Kennedy (source: The Kentucky Fried Movie). As an immigrant, this was news to me, and it absolutely fascinated me. I headed for the library to read more, and amongst some rather dubious books, I discovered this gem. As a mathematician, my instinct was to try to find the out the truth, rather than confirm my own theories. This was the only book I could find where the author seemed to share my objective. I recall he presented all the facts he could find, even ones that may have supported the lone gunman theory, and debunked some ludicrous conspiracy theories as well. (I think that perhaps some of those really off the wall JFK conspiracy theories are hatched by the lone gunman support group to discredit conspiracy theorists in general.)
So after reading this book, you have all the information you need to see that Lee Harvey Oswald couldn't have been the lone gunman, and that the government and media didn't want you to know that. It won't tell you who killed JFK, you'll have to read "Plausible Denial" by Mark Lane to find that out, another excellent book based wholly on facts. OK, it was the CIA. I'm just waiting for a book that will tell me why.