It's A.D. 72 and once again detective-informer Marcus Didius Falco (The Iron Hand of Mars, 1993, etc.) undertakes a mission--this time for Emperor Vespasian's spymaster Anacrites--to gather information on the land of Nabatea, which Rome has ideas of annexing. Falco will also be looking for Sophrona, the water organist for his circus-owner friend Thalia who vanished one day with a group of visiting Syrians. With his elegant mistress and partner Helena, Falco is climbing a sacred mountain in the desert city of Petra when he discovers a strangled body in a cistern near the peak. The victim turns out to be Heliodorus, playwright for a troupe headed by one Chremes and including clowns Tranio and Grumio, leading man Philocrates, leading lady Phrygia, several musicians, and others. Vaguely threatened by The Brother--the master priest of the mountain, who seems aware of his mission--and certain that Heliodorus' murderer is one of the troupe, Falco accepts Chremes's invitation to replace the dead man in the company--along with Helena, of course. Traveling laboriously through terrain either hostile or hospitable, Falco and Helena become part of the troupe--coping with a second murder, almost accidentally accomplishing Falco's mission for Thalia, and eventually unmasking the killer. Falco's mind-set here is 20th-century wiseguy, a concept, riddled with leaden irony and jokey asides, that rapidly palls. Scholars of the period and of theater history may be fascinated by the lengthily detailed and no doubt impeccably researched accounts of touring companies, towns, and countryside. For others: a long, dull journey.