A novel about female friendship, betrayal and imagination from the prize-winning author of The Wilderness and All is Song Shortlisted for the 2015 James Tait Black Memorial Prize Longlisted for the 2015 Baileys Women's Prize for Fiction Longlisted for the 2015 Jerwood Prize Shortlisted for the 2015 James Tait Black Memorial Prize Longlisted for the 2015 Baileys Women's Prize for Fiction Longlisted for the 2015 Jerwood Prize In the middle of a winter's night, a woman wraps herself in a blanket, picks up a pen and starts writing to an estranged friend. In answer to a question you asked a long time ago, she writes, and so begins a letter that calls up a shared past both women have preferred to forget. Without knowing if her friend, Butterfly, is even alive or dead, she writes night after night - a letter of friendship that turns into something more revealing and recriminating. By turns a belated outlet of rage, an act of self-defence, and an offering of forgiveness, the letter revisits a betrayal that happened a decade and a half before, and dissects what is left of a friendship caught between the forces of hatred and love.