How true is 'The Truth' ?

How many of you have come across a 'true account' of something only to be left questioning the validity of the statement? My boyfriend, Lloyd, has been reading a book "Hitler's Terror Weapons - from V1 to Vimana" which uses the question, 'how close were the germans to actually building a working atomic bomb', and then attempts to go through the development of the 'V' series weapons and takes glimpses at less conventional attempts by the Nazi government to stave off defeat.

This is the point where what seems detailed factual research veers away into conspiracy-theory fantastical claims. The book attempts to describe anti-gravity devices that were successfully tested, mysterious underground complexes that no one has seen since the entrances were sealed during the war, and alien interference/assistance. In the book's defense, there are a number of references to existing books and supposed reports from Nazi Germany's leaders. However the tone of the book becomes less coherent and the segue' into 'gravity' weapons and the "Vril" are more comfortably placed in fantasy than fact.

The truth may well be that there were such projects, but if there were, why have we not seen the fruits of such. Conspiracy theorists want us to believe that the world is divided into those who 'know' the truth and profit from it's obscurement, and those who do not. Lloyd's feeling is that if such were actually the case, we would see other evidence of such, rather than just word-of-mouth hearsay. The 'truth' of this book? Another case of how much one is willing to believe the highly imaginative, yet unsubstantiated claims in the book, versus what IS known and documented.