In 1200 BC ancient Greece, King Amphitryon of Tiryns invades Argos. Amphitryon eventually fights rival King Galenus in personal combat, killing Galenus and seizing his kingdom. Queen Alcmene is disgusted by her husband's thirst for power and warmongering. She prays to Hera for guidance and Hera, wife of Zeus, tells her that she will allow Zeus to impregnate Alcemene with the savior of her people, a demi-god son to be named Hercules. The only other witness to this is Chiron, the queen's loyal adviser. Amphitryon names his new "son" Alcides, though Alcmene secretly acknowledges his true name as Hercules.
Twenty years later, Prince Alcides (Hercules) is the lover of Princess Hebe of Crete. Hercules and his older brother, Prince Iphicles, are attacked by a Nemean lion, which Iphicles says cannot be killed, and their spears literally bounce off its hide. Hercules, no longer with spear, straddles the lion from behind and wrestles it until he's choked the life out of the giant cat. Iphicles takes all the credit and arrives at a royal banquet wearing the lion's pelt as a cloak and calls his brother a coward, though Hebe sees through this lie. At the banquet Amphitryon announces the engagement of Hebe and Iphicles, while Hercules is sent away to a military campaign in Egypt.
Alcemene tells him of his true lineage and that his name is Hercules, not Alcides. Hercules vows to return to Hebe in three moons, before her impending nuptials. He joins the command of Captain Sotiris in the Egyptian desert, where their small company is ambushed, leaving "Alcides" and Sotiris as the last survivors. When the leader of the ambush demands to know where the prince is, Sotiris gestures to the body of a slain soldier, while Hercules finally uses his gods-given name to conceal his identity as the prince. It is revealed that Amphitryon arranged the ambush to eliminate Hercules. The two are sold off as slaves to a promoter of gladiator style fights, where they excel. The two ask the promoter to take them to Greece to fight in an arena battle, where the two will fight six undefeated gladiators and potentially make the promoter a wildly rich man. When Sotiris is injured in a battle before leaving for Greece, Hercules convinces the promoter to set Sotiris free and he will fight all six gladiators himself. Sotiris secretly follows him to Greece.
Alcmene and Hebe mourn the death of Alcides/Hercules. When Alcmene seeks guidance from Hera, Amphitryon discovers her and learns the truth of Hercules' parentage and that he is fated to overthrow him. Amphitryon stabs Alcmene with her own dagger, then tells Chiron that the Queen committed suicide in her grief. Meanwhile, Hercules arrives in Greece and easily beats the six gladiators in battle. The people celebrate his victory and deserters of Amphitryon's army join him and Sotiris.
Hebe is in anguish after the death of Alcides and dreads her pending wedding to Iphicles. She tries to leap off the roof of the palace but is saved by Chiron, who brings her to Hercules. Amphitryon's army begins to desert him, forcing him to hire foreign mercenaries when Hercules and Sotiris begin a fight against Amphitryon's campaign of tyranny. Iphicles threatens Sotiris' son's life, forcing Sotiris to lead him to Hercules. Iphicles is surprised to discover that Hercules is Alcides. Hercules is chained and publicly flogged, then watches in horror as Iphicles murders Chiron under Amphitryon's orders. In anguish he acknowledges Zeus as his father and calls upon him for strength. Hercules breaks free from his chains and kills Amphitryon's guard, though Amphitryon and Iphicles escape.
Hercules and Sotiris raise an army and storm Amphitryon's palace. Amphitryon's palace guard join Hercules and his army and they battle Amphitryon's mercenaries. Hercules calls upon his father who infuses his sword with the power of lightning. Hercules defeats the mercenaries with his lightning sword, then meets Amphitryon in personal combat. Hercules nearly defeats Amphitryon but Iphicles holds Hebe hostage and threatens to kill her if Hercules does not let Amphitryon go. Hercules hesitates but Hebe thrusts the dagger through her shoulder, killing Iphicles. Hercules finally avenges Alcmene's death and kills Amphitryon with the same blade that killed his mother. Hercules rushes to Hebe's side as she slowly drifts into unconsciousness. Nearly a year later, the cries of a baby are heard, Hercules' and Hebe's baby boy. That night, he watches over his kingdom, finally fulfilling his destiny.
On Rotten Tomatoes, the film holds a 3% rating, with an average rating of 2.3/10, based on 71 reviews. The site's consensus reads: "Cheap-looking, poorly acted, and dull, The Legend of Hercules is neither fun enough to qualify as an action movie nor absorbing enough to work on a dramatic level". On Metacritic, the film has a score of 22 out of 100, based on 19 critics, indicating "generally unfavorable reviews".
The Legend of Hercules grossed $8,868,318 in its opening weekend, ranking #3 in the domestic box office behind Lone Survivor's third weekend and Frozen's eighth. As of March 9, 2014, the film has grossed $18.8 million domestically and an additional $42.4 million internationally for a worldwide total of $61.3 million, failing to make back the budget of $70 million.