Visible crew/equipment: In the shot of Hector as he lies dying, there are shadows on his chest plate that are not his own, nor do they belong to Achilles - must be the camera.
Continuity mistake: When Paris and Menelaus face each other and then begin to fight, the shadows keep changing, and when the camera angles show each man's perspective, each man has his shadow to his own right hand side, even though they are opposite each other.
Continuity mistake: At the start of the first battle when we see Achilles' soldiers penetrate the sands of Troy, Achilles throws a spear through a guys head. But if you look closely at the previous shot, the soldier's body is side-on, obviously so he can shoot the arrow, yet when it cuts to the spear going through the head, the soldier is completely facing Achilles.
Continuity mistake: When Briseis runs to Paris and shouts, "Paris! Don't!" in the wide shot, Achilles limps near the dead soldier on the grass. When Achilles is hit with the final arrow he drops to his knees and behind him an arrow lies on the ground (it is the 2nd arrow that hit him, which he pulled out and threw), opposite the dead soldier, which was much farther back in the previous wideshot of the grass.
Revealing mistake: Throughout the movie, especially in the scenes which take place in the Troy encampment, no matter how many times Achilles gets dirty in battle and then cleans up, there is always a small smudge on his left upper arm. In the right light, you can make out the distinctive, small, circular scar of a small pox vaccination right where that dirt smudge is - it's really quite distracting. Until 1972 in the US this was a common vaccination given to children.
Continuity mistake: Hector's sword slice,s Achilles's armor but the one shot shows the hit much higher up near the right shoulder than when we see a close up view and the cut is down by his ribs.
Continuity mistake: While still in Sparta, when Helen stands up after Paris rubs her neck, the strap of her dress on her right shoulder is closer to her neck when she removes the dress, than in the previous shot.
Continuity mistake: After Paris is given the sword of Troy, it cuts to Hector speaking to Andromache. In this wide shot the cloth draped small bed between the two large columns is turned at a slant. Yet when Hector leaves their room (before encountering Helen), the bed is now parallel to the short wall (which faces the sea).
Revealing mistake: Hector's sword is secured to the underside, from hilt to point, entirely under the shield, perpendicular to the handle he always holds. While Achilles and Hector duel, Hector snaps Achilles' spear with his leg. At the start of the next shot, Hector holds the grip of his sword and pulls it from the shield, above and parallel to the handle, not from where it should have been, obviously deliberately done to ready the sword for the shot.
Factual error: Probably the most common mistake in all the ancient warfare movies like Troy. The thick leather armour that soldiers wear is almost impossible to pierce with such crudely sharpened swords but they always seem to pierce the armour with effortless ease.
Continuity mistake: When Hector says goodbye to Paris and kisses his forehead, the small decorative gold clasps and the very large clasp at the bottom of his hair are visible. Then when Hector says goodbye to Andromache and Scamandrius, the large clasp is a completely different one and the small clasps' positions differ. The clasps in Hector's, Paris', and others, hair change position in consecutive shots throughout the film.
Continuity mistake: Menelaus' head rotates between shots of him saying "May the gods keep the wolves in the hills and the women in our beds" when at Sparta.
Continuity mistake: When Agamemnon says, "I always thought my brother's wife was a foolish woman," he is holding a whip in his hand that faces away from his right side. However, in the next shot the whip is closer to his chest, facing forward. Only visible on VHS and fullscreen DVD.
Continuity mistake: When Priam sits on the throne, with Hector and Paris beside him, as Glaucus says, "If they want a war, we will give them a war..." the flames burn brightly in the two torches standing within the doorway behind the throne. However, when Priam asks, "Glaucus, you have fought with me for forty years, can we win this war?" there is NO flame in the torch on the right side of the doorway - visible behind Hector ONLY on widescreen DVD. Yet when Glaucus says, "...and we have Hector," the flame burns brightly once again. (This is not due to the flame flickering.)
Continuity mistake: After Achilles stabs Hector with the spear, as Hector falls to his knees in the close-up, his greaves and shoes are entirely dusty/dirty - causing the dark sandals to be very light. However, as Achilles ties the rope around Hector's ankles in the close-up, Hector's greaves and sandals are now relatively clean and note the interesting pin-dot tread on the rubber soles of Hector's sandals.
Continuity mistake: As the Greeks start emerging from the 'Trojan' horse, two small staircases in the distance, to the right, is seen here and in the close-up of Achilles just as he reaches the ground. Later, after a close-up of the large white statue falling towards the camera, two shots later the 'Trojan' horse stands in the foreground and right behind the running Trojans and Greeks are those two small staircases. However in this shot the 'Trojan horse is much, much closer to that side of the temple square.
Revealing mistake: As Hector holds his son, the first warning gong is rung. In the next shot, when Hector hands the baby to Andromache, its small shiny bald head is quite a giveaway that it's really a doll in this shot (not visible on widescreen DVD). Later, Andromache holds her son, Scamandrius, when she finds Helen and Paris, as Troy burns. Aside from the fact that the door hits the back of the baby's head, he now has a bald shiny head, whereas he had hair in previous shots, so it's quite obvious in this shot that the baby is a doll once again.
Revealing mistake: Many of the spear tips and swords bend like rubber, some at almost a 90° angle and are fine in the following shots! Such as when Achilles' spear tip bends as it makes contact with Hector's shield, once when Achilles does his leap into the air at the start of the duel and then just after slicing Hector's spear with his shield. (Although weapons were made of bronze in those days, and were likely to bend, the fact that the weapons in the film bend to such a degree and then right themselves is impossible.)
Visible crew/equipment: When Achilles mounts his horse, the boy hands him his helmet and then his shield. After he says, "The Thessalonian you're fighting..." at the start of the close-up when the boy has his hands up as he gives him the shield, the grey mic is visible right under the neckline of his outfit.