A group of 300 Spartans defend a pass against the Persian army.
Sentry 1 - Dylan Scott Smith
Sentry 2 - Maurizio Terrazzano
Spartan General - Robert Paradis
Statesman - Frederic Smith
Spartan General 2 - Jere Gillis
Girl at Market - Maeva Nadon
Potter - David Schaap
Contortionist - Sandrine Merette-Attiow
Slave Girls - Genevieve Guilbault, Bonnie Mak, Amelie Sorel, Caroline Aspirot, Gina Gagnon, Tania Trudell, Stephanie Aubry, Mercedes Leggett, Stephania Gambarova, Chanelle Lamothe and Sabrina-Jasmine Tuazon
Transsexual (Asian) 1 - Manny Cortez Tuazon
Transsexual (Asian) 2 - Cindy
Transsexual (Arabian) 3 - Atif Siddiqi
Giant With Arrow - Camille Rizkallah
Litter Bearer/Slave - Neon Cobran
Dilios explains how a Spartan Baby is inspected by a Spartan Baby Inspector to see if the child has any defects, in which case he would be discarded. As Leonidas @7/8 grew he would learn to fight with a sword by Leonidas' Father as Leonidas' Mother watched. He was taught that death on the battlefield for Sparta was the greatest glory. At age 7, Leonidas was taken away and taught how to fight by being pitted against other Spartan Boys at the agoge. As he grew older he was taught to show no pain as he was lashed by Spartan with Stick. His final test was to be thrown into the wild and forced to fend for himself. If he survived, then he was accepted as a Spartan. Leonidas manages to do this by luring a wolf into close quarters in the cleft of a cliff. He returns and eventually becomes the king of Sparta. Dilios continues the tale of how a new beast is looking for a feast, but this one made of men.
Messenger rides with a group of Persians to Sparta. When he arrives he pulls a handful of crowned skulls from his saddlebag and shows them to the Spartans nearby. Captain walks into the palace as Gorgo watches Leonidas training Pleistarchos. Before leaving to speak to the Messenger, Leonidas tells Pleistarchos that the true strength of a Spartan is the warrior next to him. Theron and the Messenger walk to the palace along with the Messenger's Persian bodyguards. Theron introduces the Messenger and before the Messenger speaks, Leonidas warns him that everyone, even a king's messenger is held accountable for what they say. The Messenger tells Leonidas about the greatness of Xerxes and his armies and that all that he requires from Leonidas is earth and water as a token of Sparta's submission to Xerxes. Leonidas tells the Messenger that if the philosopher Athenians have already rejected Xerxes demands, then due to their reputation, the Spartans must also. The Messenger stops Leonidas and warns him to choose his words carefully as they might be his last as king and Leonidas looks around and glances at Mother at Market, Daughter at Market (3/5 Years Old), Spartan Boy, Boy 1 at Market, and Gorgo. He pulls out his sword, and after the Messenger tells him what Leonidas is doing is madness, Leonidas yells "this is Sparta" and kicks the Messenger in a well, followed by his Persian bodyguards.
Leonidas climbs a cliff to speak with the Ephors. Ephor 1] welcomes Leonidas and tells him they expected him. Leonidas tells Ephor 1, Ephor 2, Ephor 3, 4 and 5 about the invading Persian army and Ephor 2 demands to see what bribe Leonidas has brought. Leonidas tell them he wishes to go to war with the Persians and Ephor 1 and Ephor 2 reminds Leonidas that the Carneia will start soon. Leonidas yells that the Spartan people will be made slaves if the Persians are allowed to attack and he tells them his plan to funnel the Persians into a pass called the Hot Gates. Ephor 1 tells Leonidas they must consult the Oracle Girl. The Oracle Girl dances and then collapses. She whispers and Ephor 1 tells Leonidas that Sparta will will fall if they go to war and he must honor the Carneia. After Leonidas leaves, Theron and a Persian walk out of the shadows and give the Ephors a large sack of coins and the Persian tells the Ephors that when Sparta falls, they shall be given even more gold and new oracles delivered to them daily. During the night, Leonidas tells Gorgo that he worries that the Oracle Girl's word will cause him to lose everything and Gorgo assures him he should do what any free man would do. The next day, Leonidas walks out of the gates of Sparta and meets up with Captain and a group of 300 Spartans who all have had sons to continue their name. Leonidas inspects the men, including Dilios, and Stelios yells that they are all with Leonidas, Sparta and freedom. Leonidas sees Astinos in the group and Leonidas tells Captain that Astinos is too young, but Captain tells Leonidas, he has other sons to replace Astinos. Theron walks up along with Elder Councilman and Councilman and Elder Councilman and Councilman tell Leonidas that the Oracle Girl has spoken and they shall not march into battle. Theron reminds Leonidas that the Oracle Girl's word is the law and Leonidas tells him he is going for a walk and the others are his personal bodyguard. Leonidas says goodbye to Gorgo and Pleistarchos and Gorgo gives him her necklace and tells him to come back with his shield or on it.
As the group of Spartans march, Ephialtes watches them. They come across Daxos and a group of free Greeks. Daxos comments on the small amount of Spartans and Leonidas starts asking the free Greeks what their profession is. After hearing from Free Greek-Potter, Free Greek-Sculptor, Free Greek-Blacksmith, and Free Greek-Baker, Leonidas asks his men what their profession is and then tells Daxos, he brought more soldiers. Astinos tells the others that they are being followed and Leonidas and the others see Ephialtes on a hill. Stelios sees a village on fire and they enter the village and find it destroyed by the Persians. Burned Village Child walks up to Leonidas and then collapses and dies after telling him what happened to the village. Dilios tells the others he found the dead villagers and the Spartans and free Greeks stare in disgust at a tree with the villagers' bodies nailed to it. They march into the Hot Gates and see the Persian fleet floating nearby. During the night, a storm hits and destroys a number of Persian ships. Loyalist visits Gorgo and she asks him to help her speak to the council and he agrees to help her. A Persian Emissary being carried by a group of litter bearers is brought to Leonidas and demands to speak with whoever is in charge. As he threatens the Spartans, he notices the wall they are building is partially made of dead Persians. Stelios tells the Persian Emissary that they have killed his scouts and as the Persian Emissary tries to whip Stelios, Stelios cuts off the Persian Emissary's arm. The Persian Emissary tells Stelios that they will die while their families will be slaves and the Persian Emissary is sent away.
As Captain is talking with Leonidas, Ephialtes walks up to them and introduces himself to Leonidas and tells him he is a Spartan and his family fled Sparta when his mother decided not to kill him as a baby. Ephialtes asks to join the Spartans, but Leonidas shows him that he wouldn't be able to fight within their formation due to his deformities, but offers Ephialtes a job of bringing water to the soldiers and helping the wounded. After Leonidas leaves, Ephialtes throws away his shield and yells that Leonidas is wrong. Persian General 1 rides in front of a group of Persian soldiers and tells the Spartans to throw down their weapons, and is then killed by a thrown spear. The Persians attack and are repelled. After arrows are shot at the Spartans, a group of Persian cavalry attack and are all killed. Blacksmith points Gorgo in the direction Pleistarchos ran to and Gorgo meets with Loyalist again. He tells her she will be allowed to speak to the Council in two days and then warns her that she must make Theron her ally. Xerxes rides toward the Spartans on a giant litter and Leonidas goes to meet him. Xerxes offers peace with Leonidas and offers to make him one of his warlords if will kneel before him, but Leonidas refuses. In the evening, a group of Immortals along with Uber Immortal (Giant), attack the Spartans and manage to kill a few Spartans. The Uber Immortal attacks Leonidas and manages to wound him, but Leonidas cuts off his head. The Arcadians and Daxos help in the battle and they manage to defeat the Immortals. The battle continues the next day with the Spartans fighting giant rhinos and robed men throwing incendiary devices. For his failure, Persian General Slaughtered is executed by Executioner. The battle continues with elephants used against the Spartans. During the battle, Astinos gets his head cut off and the Captain kills a group of Persians in battle in revenge.
In Xerxes' tent, Ephialtes is led to Xerxes, walking by Long Neck Woman, Kissing Concubines, Dancers, and Armless Concubine. He is told by Xerxes that he will have any pleasure he desires and Ephialtes agrees to lead Xerxes' army behind the Spartans using the sheepherder's path. Gorgo has a meeting with Theron and he tells her that she will not be able to sway the council and offers to help her if she has sex with him and she agrees. After the battle, Dilios tends to his now damaged left eye. Leonidas walks up to him and asks how the Captain is doing and Daxos rides up and tells Leonidas that Ephialtes has betrayed them and is leading the Persians behind them. Daxos then leaves with his men. Leonidas gives a speech to his men and the Captain tells Leonidas he regrets not telling Astinos that he loved him. Leonidas orders Dilios to return to Sparta and to tell the Spartans their story and gives him Gorgo's necklace to give back to her.
Gorgo goes before the council, including Partisan, and asks them to send the entire Spartan army to help Leonidas. Instead of supporting her like promised, Theron speaks against Gorgo and Leonidas and tells the council that Gorgo offered herself to him, but he resisted. Loyalist calls Theron's claims outrageous and Theron accuses Loyalist of having sex with Gorgo in exchange of Loyalist setting up the council meeting. Gorgo takes the sword from Other Council Guard and stabs Theron in the stomach and a pile of Persian coins fall from Theron. Loyalist calls Theron a traitor and the rest of the council chants traitor. The Spartans are surrounded by the Persian army and Persian General 2 walks up and says Xerxes has come to admire the Spartans for their fighting spirit. Ephialtes pleads with Leonidas to surrender and Persian General 2 tells Leonidas he and his men will live if he kneels to Xerxes. Leonidas drops his armor and weapons and kneels before calling out to Stelios, who jumps off Leonidas' back and stabs Persian General 2 with a spear. Leonidas throws his spear and it slices Xerxes across the cheek, proving he is not a god. Leonidas and the Spartans are then slaughtered. Before dying, Stelios tells Leonidas it was an honor to die by his side and Leonidas tells him it was an honor to live by his. Leonidas calls out to Gorgo and is then shot with hundreds of arrows. Dilios reaches Sparta and gives Gorgo her necklace, who then gives it to Pleistarchos. Dilios goes in front of the council and tells them the 300's story. Almost a year passes and Dilios continues to tell the story to the Greeks now gathered at Plataea.