John Denver was America's biggest-selling solo star of the '70s. In commercial terms he was on a par with Sinatra in the '40s, Elvis in the '50s and the Beatles in the '60s. He experimented with a variety of styles and won fans from such diverse worlds as folk, pop and country music. Beneath the often tranquil surface of his music and his clear, clean tenor voice, however, lurked a darker side to ...