When animal-rights activists uncover a long-dead uniformed body in the grounds of Wanwood House, a research facility, Dalziel is presented with a seemingly insoluble mystery. And he is further perplexed when he's attracted to one of the campaigners – now implicated in a murderous assault. Meanwhile, the death of his grandmother has led Peter Pascoe to the battlefields of World War I and the enigma of who his grandfather was – and why he had to die.