During the
Siege of Alesia in 52 BC,
Centurion Lucius Vorenus of the
13th Legion commands his men as Gallic warriors fall on his
line. In contrast to the Gauls' chaotic charge, the Romans fight using a tight and well-organized shield wall, until one drunk
legionary,
Titus Pullo, breaks ranks and charges into the crowd of Gauls. Vorenus rescues and angrily orders him back into formation, and Pullo strikes him. Later, the assembled soldiers watch as Pullo is flogged and condemned to death for his disorderly conduct. The day after, the Gallic chieftain
Vercingetorix is brought before
Julius Caesar and made to surrender, ending the eight-year-long
Gallic Wars. Caesar's niece, Atia of the Julii, orders her son
Octavian to deliver a horse she has purchased straight to Caesar in Gaul to ensure that he remembers them above all other well-wishers. Caesar himself receives news that his daughter Julia, married to his friend
Gnaeus Pompeius Magnus with whom he shares power in Rome, has died in childbirth along with her
stillborn daughter. Fearing the loss of their friendship, Caesar and his general,
Mark Antony, muse that they must find Pompey a new wife. In the
Roman Senate,
Cato the Younger moves that Caesar is stripped of his command and recalled to Rome to answer charges of abusing his office and illegal warmongering. Pompey, as sole
Consul present, vetoes the motion and declares his faith in Caesar's leadership. At the theater that night, Metellus
Scipio introduces his daughter
Cornelia Metella to Pompey as a prospective wife, while Cato warns him that he must ally against Caesar before it is too late. Pompey again asserts that Caesar means no harm, although privately, he is troubled by Caesar's rising prestige and gives orders to one of his slaves who is leaving on a trip to Gaul. At night in the encampment of the 13th Legion, the
Aquila is stolen by Gallic brigands. To avoid a potentially disastrous drop in morale, Antony orders Vorenus to retrieve it. As Vorenus feels the mission is doomed to failure, he has the condemned Pullo released from the stockade to assist him. In camp, Caesar welcomes
Marcus Junius Brutus, his unofficial stepson whose mother is Caesar's lover,
Servilia of the Junii. Later, at a party hosted by Servilia, Brutus confides to Pompey that the loss of the eagle has induced the 13th Legion to plot mutiny against Caesar. On the road to Caesar's camp in Gaul, Octavian is abducted by highwaymen. For Caesar's request, Atia instructs her daughter
Octavia to marry Pompey by first divorcing her husband
Glabius, despite Octavia's protests that they are deeply in love. Atia then presents Octavia to Pompey at a party and offers her for premarital relations, which Pompey takes advantage of. Vorenus and Pullo set off in search of the eagle, encountering and rescuing Octavian from his captors. Octavian thanks them and promises that they will be rewarded. Vorenus and Pullo discover Pompey's slave trying to escape with the eagle in a cart, realizing that Pompey arranged the theft to discredit Caesar. A politically astute Octavian notes that his uncle will be quick to exploit the situation: Civil war between Caesar and Pompey is inevitable, but Caesar needs Pompey to make the first move so as not to appear the aggressor; Pompey is likely to do that if he believes Caesar's soldiers are on the verge of desertion. The trio returns in triumph to camp, where a surprised yet grateful Caesar takes the eagle back as proof of Pompey's hostility. He sends Pompey the head of his slave and informs him of his next move, to winter the 13th Legion at
Ravenna on the Italian border, while making it clear that he intends to press his right to the Consulship. Pompey breaks all ties with Caesar and takes Cornelia as his new wife. Octavia, humiliated at being used by Pompey and heartbroken over her pointless divorce, says she wants him dead. ==Production==