That in 1748 novelist Henry Fielding, then a London magistrate, formed the Bow Street Runners--the precursor of Scotland Yard--is just one of the enjoyable curiosities that Jeffers (Who Killed Precious?, 1991, etc.) presents in this lively account of England's famed police force. Ninety years after Fielding's innovation, the Runners, who never numbered more than 15, faced a criminal army of 30,000--reason enough for Home Secretary Robert Peel to order the formation of a Metropolitan Police Force, to be housed at 4 Whitehall Place, allegedly once ""the site of a palace for visiting Scottish royalty"": And so Scotland Yard was born. By highlighting celebrated cases and personalities, Jeffers sets out to show that the popular image of Yarders as ""inept and ineffectual""--an image summed up, he points out, in Sherlock Holmes's foil Inspector Lestrade--does disservice to a highly professional and dedicated police force. For the most part, Jeffers succeeds, though the first case he presents to counter that image--the solution of the murder of a young woman found stuffed into a car trunk at Gatwick Airport in 1991--points up that it's dogged gumshoeing rather than Holmes-like inspiration that most often allows Scotland Yard to get its man--or, occasionally, woman. Dozens of earlier cases then roll by, a few too familiar--Jack the Ripper, Dr. Crippen, the Keeler/Profumo spy/sex scandal--but many not, and with a preponderance of bloody bodies, often chopped up; and with these cases, interesting notes on the evolution of police work, particularly the advent of forensic detection and the need to combat a new class of gun-toting criminals, including terrorists. No milestone in criminological history but, rather, light, knowledgeable, appealingly ghastly fare for true-crime buffs.