Baltimore Sun reporter Simon spent a year tracking the homicide unit of his city's police, following the officers from crime scenes to interrogations to hospital emergency rooms. With empathy, psychological nuance, racy verbatim dialogue and razor-sharp prose, he offers a rare insider's look at the detective's tension-wracked world. Presiding over a score of sleuths is commander Gary D'Addario, "connoisseur of survival" who grapples with political intrigue, massive red tape and "red balls" (major, difficult cases). His detectives include Tom Pelligrini, obsessed with solving the rape-murder of an 11-year-old girl; Rich Garvey, whose "perfect year" is upset by a murder case that collapses in court; and black, cosmopolitan Harry Edgerton, a lone wolf, son of a jazz pianist. This hectic daily log reveals the detective's beat on Baltimore 's mean streets (234 murders in 1988) to be brutal, bureaucratic and, occasionally, mundane