Just ten pages into The Triumph of Caesar, I had learned more Roman history from Steven Saylor than from all my high school and college professors combined. “Haruspicy was the Etruscan science of divination.” “Cato [was] leader of the opposition’s last stand against Caesar in Africa.” Indeed. In this twelfth book of the acclaimed Roma Sub Rosa series, Gordianus the Finder (whose partnership with wife Bethesda is very much a tunic-clad version of Nick and Nora Charles’s) is persuaded by Caesar’s wife, Calpurnia, to investigate a possible conspiracy to assassinate her husband. Calpurnia’s haruspex confirms her fear that the attack will happen during one of the four upcoming citywide “triumphs,” or massive celebrations of Caesar’s victories in Gaul, Africa, Egypt, and Asia. Phone and Internet service being sorely lacking in ancient Rome, the nearly retired 64- year-old sleuth trudges the city’s streets to gather information the old-fashioned way—usually over a cup of wine in a shady villa. Saylor is no slouch—he whips up more than enough plot, character, and suspense to carry the mystery to a satisfying conclusion—but it’s the historical backdrop and detail that set The Triumph of Caesar apart. Veni, vidi, legi. St. Martin’s Minotaur, $24.95