In 52 BC, the Roman Republic was at its peak. The consul Pompey (Rick Warden) guarded the capital, and his ally Caesar (Ciarán Hinds) fought in Gaul. During this period, the 13th Legion repeatedly made military achievements. The commander Urienus (Kevin McKidd) was brave and resourceful, and his subordinate Polo (Ray Stevenson) was addicted to alcohol but loyal and courageous. When Caesar won, Octavian followed his mother's order to go to the front line to express his condolences, but he was robbed on the way and was rescued by Urienus and Polo who passed by. The 13th Legion returned triumphantly, and Urienus met his wife who had been away for 8 years, but they had their own thoughts. Polo accidentally discovered that Urienus's wife was having an affair. In order to protect the reputation of his superior, Polo forced out the truth with the help of Octavian. Caesar was ready to take power and waited for the opportunity. Pompey saw his ambition and discussed with the Senate. The aristocratic forces led by Cicero insisted that Caesar was a traitor to the Republic and should be killed. At this time, Caesar's general Antony (James Purefoy) took over as the tribune and started to deal with Pompey's group...