Henry Grossman didn't make The Beatles pose for his shots. "I simpy watched," he says. As a trusted friend to the group from 1964 to 1968, the Life photographer gained unprecedented access into their lives—traveling around the world and snapping over 6,500 images, many still unseen. In his new book, Places I Remember: My Time With the Beatles, Grossman reveals over 1000 of those photos. In this image, he captured the band mid-recording session for what would come to be one of their greatest achievements: Sgt. Pepper's Lonely Hearts Club Band. See more photos here.