Detective Murdoch finds himself investigating his own father, Harry, for murder when the body of John Delaney is found soon after the two had an argument in a pub. Harry had complained that the ratting contest in the pub was fixed and was thrown out on his ear. Murdoch's father is a drunkard and down and out and there is no love lost between the two. He believes his father was responsible for his mother's death and they have not seen each other for many years. In his investigation, Murdoch is helped by an idiot savant who works at the pub and has a fixation on time. Using that information, the detective builds a detailed time line for the crime, finally identifying the anomaly that leads to the killer.