First gaining renown as the voice of Portishead, Beth Gibbons is an enigmatic yet intensely emotional musician. Portishead's innovative version of trip-hop drew on the vocal jazz and pop of the past while reinventing it radically, and Gibbons' vocals -- which recalled bygone greats such as Nina Simone and Edith Piaf -- fit the group's postmodern mystique perfectly. As a solo artist, Gibbons places her elegant-yet-gritty contralto in a wide array of settings: The haunted chamber folk of 2002's Rustin Man collaboration Out of Season was a departure that nevertheless felt true to...