Late in the summer of AD 168, Thais Cato and her family are vacationing at their seaside villa. Thais stumbles upon two runaway gladiators and helps them escape without her parents' knowledge. Now, realizing that one of the gladiators is in on a plot to assassinate the emperors of Rome, Thais must race against time to warn the emperors of the new threat and save Rome from a battle they cannot win.