There''s a myth attached to ''A Hard Day''s Night'': the Byrds adopted the 12-string guitar and transformed ''Mr Tambourine Man'', Dylan went electric as a result, and a pattern of intense competition climaxed with the release in quick succession of Blonde on Blonde, Pet Sounds and Sgt Pepper. A closer look tells us something different. Dylan''s electric ''Subterranean Homesick Blues'' preceded the Byrds'' version of ''Mr Tambourine Man'', which owed just as much to the Beach Boys - whose epochal Pet Sounds came out a full year before Sgt Pepper. Using timelines derived from release dates, studio sessions and personal encounters, Play It Hard traces the paths of influence during a 3-year period when artists crosspollinated via recordings, rivalry, rumours and drugs - changing music forever.