The past is never truly buried. These four novels share an unsettling premise: that a case filed away, a death written off as random, a crime absorbed quietly into history, is never fully closed. Porteous, Bosch, Grace and Rebus share little beyond a particular stubbornness, a refusal to let a case stay closed when the evidence says otherwise. They carry the weight of a truth someone has gone to considerable lengths to conceal. Read them for the plotting; stay for the detectives.
Ann Cleeves, 'The Sleeping and the Dead' - When a diver finds a teenager's body perfectly preserved after two decades in a Northumberland lake, detective Peter Porteous traces the cold case back to the woman who was with Michael Grey the night he disappeared.
Michael Connelly, 'The Black Box' - Twenty years after Danish photojournalist Anneke Jespersen was shot dead in the chaos of the 1992 LA riots, a single ballistics match convinces Harry Bosch her killing was planned and the perpetrator still free.
Peter James, 'Dead Simple' - When the friends who buried groom Michael Harrison alive as a stag-night joke die in a crash moments later, Detective Superintendent Roy Grace has three days to the wedding and no idea where to dig.
Ian Rankin, 'The Hanging Garden' - When a gangland war breaks out across Edinburgh while Rebus pursues a suspected Nazi war criminal, a professional hit-and-run that nearly kills his daughter makes clear just how far the violence is prepared to reach.