Eight books into British author Rowe's acclaimed mystery series set in second-century Roman Britain (Enemies of the Empire
, etc.), her period detail, plotting and characterization are as strong as ever. A string of suspicious coincidences make Libertus, a former slave turned mosaic maker and sleuth, the prime suspect in the kidnapping of the wife and son of his patron and protector, Marcus Aurelius Septimus. Struggling with illness, Libertus must also defy the accusations of a crafty Greek physician, who has gained Septimus's confidence, to track down the criminals and save two lives. Though not well known in the U.S., Rowe more than holds her own with the two leading authors of ancient Roman historicals, Lindsey Davis (the Marcus Didius Falco series) and John Maddox Roberts (the SPQR series). (Oct.)