We'll probably never know what the hell Yoko Ono was thinking when she persuaded her knockout assistant May Pang to get it on with her husband in the summer of '73. What started out as a "lost weekend" with John Lennon turned into a year-and-half-long affair, a period the Beatle later called "the happiest I've ever been." Pang has few regrets, but what she does have are some great photographs, seen for the first time in her new book, Instamatic Karma. Lennon later admitted he was "fucked up on booze and shit" most of the time; perhaps that state of inebriation led to the unguarded moments—swimming, smoking, stuffing his face, wearing his girlfriend's pants—that come through in Pang's pics. Obviously, it was good shit.