Setting is outlined as a further fictional character, however well based on an actual place. The ways it can determine mood and atmosphere, and bring a fiction to life, are explored. However, of fundamental importance, as outlined, is the idea that it is the point- of-view characters who do the seeing, the observing. Setting in crime fiction is determined by characterisation, and the mood emanating from particular characters. Setting does not exist omnisciently, or independently from the plot. Examples of highly effective description from Ian Rankin, Steph Cha, Elmore Leonard, Jim Thompson, Manuel Vázquez Montalbán and Maj Sjöwall and Per Wahlöö are among others are detailed. Further examination of fact, forensics and police procedure in relation to setting and generating authenticity of time and place is detailed. Period crime fiction, with mention of Stuart Turton and Eleanor Catton among others, is further examined, along with its reliability on description and effective observation. Work from Abir Mukherjee is analysed historically, while description in Henry Sutton’s novel My Criminal World is practically detailed.