One can always trust the police to be dogged and to keep voluminous records, though they’re not always accurate. Holly Tucker was able to write her new book—City of Light, City of Poison: Murder, Magic and the First Police Chief of Paris—because Nicholas de La Reynie, the French top cop, keep his own records of his investigations into criminal matters in the 17th century. His boss, Louis XIV, burned the only other copy, probably to cover up the crimes that rocked his throne from about 1665 to 1670.

In that five-year period, the criminal and the civil lieutenant of Paris were both murdered, just a year a part. In 1665, Jacques Tardieu, the criminal lieutenant, was stabbed to death in the course of a home invasion, as it would be called these days. Two brothers, Rene and Francois Touchet were arrested, charged with murder, found guilty, and executed in public before a large crowd that watched the spectacle . . .