The story picks up from where The Face of the Deep ends. Douglas Romer has returned to Dingle, Ireland, and continues to be on sick leave following his breakdown. He is stronger following the transforming experience of Gethsemane, and yet is haunted by the fact that the killer of his wife may be turning his sights on Douglas. Once again he teams up with his friend, Dorchadas, the retired angel, and with other friends he has made in Dingle. He also encounters some other characters who, until now, he only knew as figures from the past. As the story progresses, Douglas becomes increasingly aware of the force of dark powers bearing down upon him. How will he and his friends resist their destructive force?