Cat Stevens wrote this album while hospitalized for tuberculosis. He wasn't an international star yet, but here the elements fell into place: the acoustic sound and sparkling production, the spirituality and mystery. There's a dark undertow on "Lady D'Arbanville," an unlikely U.K. hit about the death of a lover, and pure elation on "I Think I See the Light." There's also some schoolboy mischief on the title song, a coy blues ditty written in tribute to a certain male appendage.