Upon a dark night - Peter Lovesey

Peter Diamond, the traditionalist dinosaur of Bath CID, finds the low murder rate in the city a touch frustrating, so he decides to check whether a couple of suicides which his colleague is investigating have been accurately classified. On the outskirts of the city a woman is found unconscious in a hospital car park, but when she recovers she can't remember who she is or how she came to be there. Soon after she is released into the care of the local authority, Diamond has a 'proper' case to get his teeth into when a woman's body is found in the garden of a flat after a somewhat drunken party. None of the other guests knew her and it is not clear whether she slipped, jumped or was pushed, and with no clue as to her identity Diamond has a puzzle to satisfy his quirky talents. In a mystery of stunning complexity, Peter Lovesey amply demonstrates his gifts as the grand master of the contemporary whodunnit.