The leading California-based vocal group of the '60s, the Mamas & the Papas epitomized the ethos of the mid- to late-'60s pop culture: live free, play free, and love free. Their music, built around radiant harmonies and a solid electric folk foundation, was gorgeous on its own terms, but a major part of its appeal lay in the easygoing southern California lifestyle it endorsed. The group's success was as extraordinary as it was brief, and onlookers may well wonder what went wrong with a performing group that seemed to have the world at its feet for all of two years. The irony b...