AD 101. Eleven years have passed since the emperor Domitian led a campaign into Dacia to chastise them for their incursions, meeting the enemy once again at Tapae, the site of an earlier battle. But Domitian is gone, now, and a new emperor sits on the throne: Trajan. This new leader of the Roman world is determined to succeed where Domitian failed: the total subjugation of Dacia.

For Tiberius Claudius Maximus, newly-assigned rider in the Roman auxilia, the new emperor’s campaigns will mean facing the ghosts of his past, for a new war awaits, and fate draws Maximus back to Tapae. This time, will the Romans crush their opposition, defeat the dreaded King Decebalus, and win control of the pass that opens up Dacia: the Iron Gates?