Midway through Sally Morrison’s new novel, Mad Meg, I began to develop the scissor twitch, an almost overwhelming urge to cut it up and reassemble it into a new structure. Not quite the vandalism it suggests – I read Mad Meg in galley pages, which encourages scissorly desires. It is a vast, kaleidoscopic novel, which opens with a wonderful mischievous energy, full of surprises and pleasures, and laconic wit. Yet it begins to teeter midway and, in my view, ends in unnecessary disarray. Hence the twitch.