After the assassination of Julius Caesar and the hunting down and elimination of his assassins, Roman general Mark Antony, Octavius Caesar and Lepidus rule Rome and its territories together as Triumvirs. Although greatly admired in Rome, Antony has chosen to live in semi-retirement with Queen Cleopatra in her country, Egypt—much to the chagrin of his followers.

With news that Pompey (Sextus, son to Pompey the Great) has raised an army that threatens the triumvirs’ power, and that his wife Fulvia has died, Antony returns to Rome. Tensions are high amongst the triumvirs as Octavius accuses Antony of neglecting his duties as stateman and military officer, but their alliance is essential to fight Pompey. Upon prompting by Octavius’s man, Agrippa, Antony agrees to show his solidarity to the triumvir alliance by marrying Octavia, sister to Octavius. Cleopatra does not take this news well.

The triumvirs then make a peace pact with Pompey, granting him control of Sicily and Sardinia, and Pompey throws a grand drinking party on board his ship in celebration. Pompey’s follower, Menas, offers to rid him of the triumvirs, and thus bestow world power upon him, by throwing them overboard. Pompey declines. An opportunity missed.

Antony sends his follower, Ventidius, to wage war against the Parthians while he takes Octavia to Athens. Back in Rome, Octavius breaks the peace with Pompey, keeping the victory spoils for himself. He then imprisons Lepidus and confiscates his property. When Antony voices his displeasure with Octavius’s actions, Octavia returns to Rome to repair relations between her brother and husband. By the time she reaches Rome, Octavius informs her that Antony has returned to Cleopatra.

As a co-ruler of the Roman world, Antony bestows additional kingdoms on her and each of their three children, and on her son by Julius Caesar, Caesarion. Octavius, great-nephew to Julius and named in Caesar’s will as his heir, sees in Caesarion an additional threat to his goal of world supremacy. He publicly accuses Antony of abandoning both his Roman wife and his country. The two men mobilize for war against each other and for control of the Roman Empire.

Antony and Cleopatra make camp at Actium on Greece’s western coast with a vast land army and a naval fleet of several hundred ships. Although a better commander on land and despite the pleas of his close friend, Enobarbus, Antony chooses to fight by sea against Agrippa who commands the superior naval fleet of Octavius. When the battle begins to look lost for Antony, Cleopatra flees in her flagship, keeping the treasury from falling into Octavius’s control. But Antony also abandons the fight to follow her—much to his later shame. Without their commander, Antony’s forces lose heart and lose the day.

The victorius Octavius sends his terms to Cleopatra: she can denounce Antony to keep her kingdom. When Cleopatra greets this messenger with her usual charm, Antony is consumed with jealousy and suspicion, and orders the man whipped. He fears her only motivation is to acquire yet another world leader, this time Octavius, as her lover.

Antony challenges Octavius to a man-to-man duel, which Octavius disdainfully refuses. Antony’s forces begin to change sides, including the devoted Enobarbus. Upon hearing of his desertion, Antony sends his friend’s belongings after him. Enobarbus, bereft of his soldier’s honour and appalled at his traitorous actions towards his dearest friend and general, dies of a broken heart.

In a land battle, Antony and his remaining forces are the victors; when the fighting shifts again to the sea, the Egyptian fleet surrenders. Convinced Cleopatra has betrayed him, Antony threatens to kill her. Thinking that only her death will appease him, she and her attendants hide in her tomb and send Antony word that she has killed herself. Devastated by her loss, Antony orders his devoted servant, Eros, to help him die as a Roman. Eros kills himself rather than kill his beloved master. Antony then attempts to die by falling on his sword, but succeeds only in wounding himself. Too late, he learns that Cleopatra still lives and waits for him in her tomb. His guard carries him to her, where he dies in her arms.

Octavius’s men burst into her tomb, taking Cleopatra prisoner. She feigns cooperation with the new Caesar until she learns from his follower, Dolabella, that he plans to parade her through the streets of Rome as his captive. A clown brings a basket of figs containing her “escape route”. Dressed in her royal attire, she clasps two asps to her and dies from their bites.

With his enemies dead and the path clear to his sole rule of the Empire, Octavius Caesar can be magnanimous. He agrees to Cleopatra’s final request that she and Antony be buried together.