Williams (The Chosen One) opens her latest novel with a bang--almost. Written in spare yet resonant verse ("Last night/ me and Lizzie/ sit/ in the dark,/ sit on my bed,/ in the quiet of/ night./ We're all grown up,/ I think./ But we are/ having us some/ troubles"), the book is told from the unreliable perspective of 12-year-old Hope, whose 14-year-old sister, Lizzie, threatens to shoot herself on page one. Lizzie is hauled off to a mental hospital, but the reason behind the suicide attempt remains unclear--even to Hope. As the story progresses, clues about the girls' upbringing are revealed in a series of flashbacks. Hope's memories paint a picture of sporadic sisterly bonding (secret club meetings in the attic, lip-synching to Jesus Christ Superstar), while other incidents (their father's death, Lizzie's crying spells, their alcoholic mother's abusive temper and prostitution) hint at a darker reality. Williams's decision to wait until the end to divulge the cause of Lizzie's misery is a gamble, but one that works. The truth-- exposed after Hope reads her sister's diary--is appalling. Ages 12¿up. (June)