This time the trouble seems to be linked to a thirteen-year-old crime that horrified London at the time, the brutal murder of a family and the apparent slam-dunk arrest and conviction of then eighteen-year-old Hannah Docherty for the murder of her mother, stepfather, and younger brother. The only problem is that the more Frieda reviews the case and after visiting Hannah at a hospital for the criminally insane, does she begin to suspect that Hannah just might not be guilty of the crime. But who committed the murder all those years ago and just how far will they go to ensure no one knows the truth is the question raised in the sixth installment in the Frieda Klein series, Dark Saturday by Nicci French.