I have been studying the JFK assassination for almost thirty years and by now have read scores of books on the case.
But why am I even mentioning this? John Armstrong's phenomenal "Harvey and Lee" does NOT deal with the actual assassination of Presiudent Kennedy! In its pages you will find no treatment of the ballistic or medical evidence nor any forays into the identification of exactly who fired the shots.
Rather, what you WILL find in this massive, profoundly-researched book is the result of years of private research performed by a great American named John Armstrong, a successful businessman who attended a college class in Texas on the assassination and who subsequently became intrigued by the "two Oswalds" theory that Professor Richard Popkin and other early researchers first posited during the 1960s.
Amazingly, at his own expense Armstrong literally traveled all over not only the U.S. but also the globe to personally interview people who'd had direct contact with the figure[s] known as "Lee Harvey Oswald" and -- perhaps even more importantly -- to obtain the ORIGINAL DOCUMENTS related to the case, many of which had never before seen the light of day or been published in any other book. (Early on the author discusses his belief that researchers should not rely on the work of others but should instead go to the original documents and evidence. Armstrong certainly practiced what he preaches, and the reader is all the more the winner for it.)
Armstrong's most essential finding -- backed-up by huge amounts of evidence, images of a small portion of which are contained on a CD which accompanies the book -- is that there were two "Lee Harvey Oswalds," a U.S.-born one who he refers to as "Lee" and a (likely foreign-born) one referred to as "Harvey." They are very, very close in appearance, so much so that, not surprisingly, those who'd had contact with them both could only harbor the slightest suspicion that they were actually two different people.
Sounds crazy, right? Absolutely.
However, as Armstrong discusses in an early chapter of the book, substituting twins or unrelated "doubles" for one another is a longstanding technique used by intelligence services; in fact, Armstrong provides examples of intelligence services' usage of just such "doubles" as recently as the 1960s (Castro's Cuba) which the reader can easily verify.
I will not continue this now hardly-brief discussion of "Harvey and Lee" because I could never come close to even tangentially touching on the truly phenomenal amount of new information provided and interviews analyzed in this book. Do yourself a favor and check out clips of some of the YouTube.com videos Armstrong did with people who had direct, personal contact with one or both of the two "Lee Harvey Oswalds."
Again, this book contains ZERO information about the actual assassination, yet in my view it is, most ironically, the hands-down most utterly intriguing and most painstakingly research-based book on, or relating to, "the case" I have ever read (and I've read the almost-1000 page book twice, although I'm planning to re-read it soon.)