Having caricatured Sherlock Holmes, Edward the VII, and most recently William Randolph Hearst (Murder at San Simeon), Hall now turns his (quill) pen on Ben Franklin--with the coy, not to mention clichÃ‰d, discovery of yet another recently unearthed manuscript, this written by an aging Nicholas Handy, recounting the awful/marvelous 12th year of his life and his introduction to the sage from Philly. Young Nick awoke one morning to discover his employer, Ebenezer Inch, Printer, hacked with an ebony-handled knife, partially scalped, and thoroughly dead. To the rescue: Ben Franklin, alas late for an appointment with the late Mr. Inch, but in time to find clues--bits of shell and a livery button. Soon Ben whisks Nick away from the unkind care of the Widow Inch and spends the next several weeks introducing the lad to crime-solving techniques, which supposedly have not been invented yet (fingerprinting, for instance). Among their discoveries: a Lord being blackmailed; a master criminal in disguise; a family of distraught Indians; a knave with two names; a warehouse full of stolen goods; a foppish son; a vicious daughter; a furious wife; a secret passageway; two other murders; and a complex genealogy that links Nick and Franklin to a sweet young thing who got pregnant in Boston and gave birth in London. And there's time left over to fiddle with electricity, meet Joseph Fielding, shiver past the Tyburn (hanging) Tree, and plead the colonists' case for taxing the Penn boys in Parliament. Rather charming in spots, and despite--or maybe because of--those flirty ladies on the barge in the Thames, most YA readers would thoroughly enjoy themselves. Adults, however, may wish to pass on this one.