"For a long time Sorrowmouth existed as three or four separate ideas in different notebooks until one day, in a flash of divine inspiration, I recognised the common ground they shared with each other. A man trekking from one roadside memorial to another, in pursuit of grief; Beachy Head and its long dark history of suicide; William Blake and his angelic visions on Peckham Rye; Blake again with The Ghost of a Flea; a monstrous companion, bound by...