For the Beatles, 1967 marks a signal crossroads that would both transform the group’s career and place them on a trajectory towards their eventual disbandment. It was a year in which they exploded prevailing rock music demographics through the global onslaught and international success of Sgt. Pepper’s Lonely Hearts Club Band beginning in June 1967. Yet it was also a period that saw them in a precarious state of flux throughout the summer and fall months, as the band attempted to recapture...