Tacitus' ``year of four emperors''--A.D. 71. Deep in war-torn Germany, Julius Civilis, chief of the rebel Batavians, has overrun the imperial fort at Vetera, slaughtered its defenders, and delivered commanding legate Munius Lupercus into the unspeakable clutches of the priestess Veleda. Picking up Munius' trail, investigating Veleda, and repatriating Julius Civilis--all is clearly a job for Vespasian's informer Marcus Didius Falco (Venus in Copper, etc.), especially since Titus, the emperor's son, has his eye on Falco's patrician girlfriend Helena Justina and would love to have her lover out of the way. All aboard, then, for druidical rites, human sacrifice, savage attacks, and some great scenery. More adventure than mystery this time, with an unmemorable supporting cast and the local color from Falco's latest travelogue overshadowing his ripe backchat--though some readers may like Falco best when he's most subdued.