In year 1250 B.C. during the late Bronze age, two emerging nations begin to clash. Paris, the Trojan prince, convinces Helen, Queen of Sparta, to leave her husband Menelaus, and sail with him back to Troy. After Menelaus finds out that his wife was taken by the Trojans, he asks his brother Agamemnon to help him get her back. Agamemnon sees this as an opportunity for power. They set off with 1,000 ships holding 50,000 Greeks to Troy.

Based on Frank Miller's graphic novel, "300" is very loosely based the 480 B.C. Battle of Thermopylae, where the King of Sparta led his army against the advancing Persians; the battle is said to have inspired all of Greece to band together against the Persians, and helped usher in the world's first democracy.

Greek general Themistocles attempts to unite all of Greece by leading the charge that will change the course of the war. Themistocles faces the massive invading Persian forces led by mortal-turned-god, Xerxes and Artemesia, the vengeful commander of the Persian navy.

Essentially true story of how Spartan king Leonidas led an extremely small army of Greek Soldiers (300 of his personal body guards from Sparta) to hold off an invading Persian army now thought to have numbered 250,000.