Continuity mistake: When Odysseus sees Aeolus' face in the waterfall, in the shots from behind, Odysseus' left sleeve is rolled up and his right sleeve is rolled down. Yet when viewed from the front, Odysseus' right sleeve is rolled up and his left sleeve is rolled down.
Continuity mistake: As the sailors cut open the sack of winds, between shots the knife they use moves further up the sack.
Continuity mistake: When Odysseus spears one of the suitors to the door, the angle of the spear changes between shots.
Audio problem: When the men are escaping from the cave, the cyclops yells "Where are you?" and pounds his hands on the ground, but the sounds that are heard don't match him pounding the ground.
Audio problem: The exact same sound of someone yelling "Bring the grain" or "Where would you like these sacks of grain?" can repeatedly be heard inside the Ithacan palace throughout the movie.
Continuity mistake: When Odysseus is about to arrive at Circe's palace, he puts his hand next to one of the cracks on the ground. Between shots his hand moves further away from this crack.
Continuity mistake: When the men are about to leave Ithaca, Odysseus raises his hands and cries "Set the sails". Between shots the blanket over his shoulder moves closer to his neck.
Continuity mistake: The blood on the cyclops' chin disappears quite suddenly, though he never wipes it off.
Deliberate mistake: The same shot of Odysseus killing a man with two swings of his sword is used twice in the battle scene.
Continuity mistake: When Telemachus is in the dark trying to string his bow, a vase with arrows in it is visible next to him. Then after he throws his bow to the ground in frustration, the arrows are gone.
Revealing mistake: Achilles takes the spear that he later throws at Hector out of a dead person's body, but the spear has no blood on it at all.
Revealing mistake: There are two points in the film where Odysseus throws a flaming torch into the air. The first was when he was at Troy. The second was a throw at Scylla. Notice that these torches make exactly the same noise and move in exactly the same way.
Continuity mistake: In the scene where Hermes is talking to Odysseus on the cliff, the nearby plants changes distinctly between shots.
Audio problem: In the cyclops' cave, Odysseus tells his men to get the wine so that they can trade it for water, but when he does this, his lips don't move.
Visible crew/equipment: During the battle scene, Odysseus' narration goes "and no one knew whose side the gods were on." In the shot where he begins to say "were on," a crew member with brown hair and a black shirt is visible behind the charging Greek army. A split second later another crew member is visible, this time with black hair and a blue shirt.
Continuity mistake: There are two shots of Odysseus floating in the water right before he reaches Calypso's island. In the first shot, you can see that he is wearing armor. In the second, his chest is bare.
Continuity mistake: When Hermes says "Heed my advice and reach that stone" Odysseus is looking at Hermes. In the next shot, as Odysseus replies "Which?" he is facing up the cliff.
Revealing mistake: After the sack of winds is opened, Eurylochus is shown grabbing onto a rope in midair, and the string holding him up is visible.
Continuity mistake: When Odysseus is hugging Calypso, the ship magically appears on the horizon.
Continuity mistake: Between shots of Menelaus saying "You, Telemachus, you must return", his arm magically appears on Telemachus' shoulder.
Answer: It's a marching chant, sort of like an ancient version of the marching music we have now.
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