Having brought home to Athens the Olympic victor's laurel crown, Phillippides becomes commander of the Sacred Guard, which is expected to defend the city-state's liberty, a year after the expulsion of the tyrant Hippias.

Theocrites instructs Miltiades to hold back the Sacred Guard to defend the temple of Pallas after a likely defeat, and proposes instead to negotiate terms with Darius, but is told an alliance with Sparta could save the Hellenic nation.

Phillippides makes the journey and survives an attempt on his life by conspirators; he returns with Sparta's engagement during the Persian attack in far greater numbers on Militiades valiant troops.

Charis, left for dead after overhearing Darius's orders, reaches the camp to tell that the Persian fleet, now commanded by the traitor Theocrites, is heading for the Piraeus to take Athens.

[3] Ten days before the premiere, director Mario Bava was forced to reshoot exterior scenes because several extras were spotted smoking cigarettes on camera.