The mesmerising new novel from the twice Booker-shortlisted author of Hot Milk and Swimming HomeIf she was my double and I was hers, was it true that she was knowing, I was unknowing, she was sane, I was crazy, she was wise, I was foolish? The air was electric between us, the way we transmitted our feelings to each other as they flowed through our arms, which were touching.At the height of her career, the piano virtuoso Elsa M. Anderson—former child prodigy, now in her thirti