Gretel hasn’t seen her mother in sixteen years. Growing up on a boat on the Oxfordshire canals, Gretel and her mother created a world of their own, with words of their own, and a creature they called the Bonak that haunts the dark currents of the river. Now Gretel is grown, a lexicographer who tries to make sense of the words of the real world whilst not being able to make sense of her own past. Too many questions are left unanswered, and she hunts hospitals and morgues searching for her mother and for answers that only her mother can give her. When the two are reunited, Gretel begins to trawl through fragmented memories and asks, what happened to Marcus? What happened to the boy that lived with us that winter?