After barely surviving a time-crossed adventure in India, at the hands of the Kali entity, the Doctor and Clara have returned to 21st Century London. But there's something not quite right. Something unsettling, in-between the cracks in the pavement and the holes in the wall. Impossible creatures dragging themselves in from the Void on the back of an experiment from a parallel universe. The Fractures are here...and they're Hungry.