In between the two great powers of Rome and Parthia lies Palmyra, a small desert kingdom. Parthia, Rome's enemy, longs to gain control of Palmyra to strengthen its base and launch an invasion of the Roman provinces. To protect the Empire, Prefect Macro, Centurion Cato and the Second Illyrian cohort prepare for a campaign. But as they seek to guard Palmyra's borders, Parthia starts amassing its armies for war. And once the Parthians attack some of the Roman outposts, Macro's cohort has no choice but to pursue the enemy into distant and treacherous territory.