6. 'The Beatles: The Authorized Biography,' by Hunter Davies
The volume many people think of – erroneously – as the first Beatles book set a high standard with its frankness. Released in 1968, The Beatles was the only place, for a long time, you could get examples of the correspondence between John Lennon and Stuart Sutcliffe. Consider these lines from a poem Lennon sent his friend: "I can't remember anything/Without a sadness/So deep that it hardly/Becomes known to me." That is Fitzgerald "dark night of the soul" territory, and it comes from a time when few people would have thought the Beatles anything but louts. Don't be put off by the authorized-access element – clearly these were guys who needed to unburden themselves of some truths they'd been toting around for the bulk of a decade, and they pile up here.