Revealing mistake: When Beni is in the tomb, the place is dark and is only lit by the candle he's carrying. However, when Beni turns around, his shadow on the ground doesn't change positions, indicating that it's not being cast by the candle, but by another source of light. (01:06:40)
Revealing mistake: The first night after O'Connell goes back to Hamunaptra with Evie, the camp is attacked. In one shot, when O'Connell is shooting at the attackers, he fires and then swings the gun to his right and fires again. As he swings the gun around the flare from the gun follows the nozzle as though it were, say, a spark on a birthday cake sparkler, definitely not like the spark on a gun.
Continuity mistake: When Rick is fighting Benny on the camel when they are riding towards the temple Rick and everything else is in shadow in some shots even though the sun is high up and there are no clouds. (00:38:30)
Audio problem: When Jonathan and Evelin are about to board the boat after Rick gets on, Jonathan says "Yes, yes, you're right. Filthy, rude and a complete scoundrel, there's nothing to like there at all." Before he finishes his sentence it cuts back to Evelin, and his lips don't move. (00:23:30)
Revealing mistake: Just after Rick shoots the sword out of Ardeth's hand, he flips over onto the ground to grab a stick of dynamite and quickly light the fuse. Look carefully, the fuse is already lit at the end and it doesn't even touch the fire.
Continuity mistake: When Henderson gets killed by Imhotep in his hotel room, the shadow of his corpse being thrown shows it to be thrown quite a distance across the room, yet when Imhotep appears, and then walks off, Henderson's corpse is right by his feet. It was thrown much further than that.
Factual error: What is the 'Royal Air Corps'? It was the Royal Flying Corps until 1918, and has been the Royal Air Force ever since. (01:09:55)
Continuity mistake: Following the attack of the Magi on the adventurer's camp, the short sighted American's shaving foam changes from shot to shot.
Factual error: The sacred jars containing Anck-su-namun's organs are protected by a pressurized salt acid booby trap. The beginning of the film depicting Anck-su-namun's death is set in 1290 BC, meaning the trap must've been installed at this time, but salt acid wasn't discovered until 800 AD. (01:08:34)
Continuity mistake: In the scene where Evie, Jonathan, Rick and the fat guy drop down into the mummy preparation room, you see the fat guy pick up his tools and start walking forward, then in the next scene, you see the exact same thing. (00:41:15)
Continuity mistake: At the beginning of the movie Anck-Su-Namun stabs herself with the knife she just used to stab the Pharaoh, but no blood is on the knife.
Continuity mistake: You'll notice that they put a lot of emphasis on the sun rising and "showing the way." The sun then rises IN FRONT of them. When the camera gives us a view of the riders on the camels, the shadows from their hats fall directly on their faces, when instead there should be no shadows. When the camera moves to show them all riding towards Humanaptra, their shadows fall a little to the left and behind, like it's high noon or something. (01:37:45)
Factual error: When Rick is running from the horsemen at the begining, he stops in front of a pillar and waits to be shot. We see the horses round the corner and rear back in fear and one falls over. We then see Rick again and then cut back to the horses, which have all disappeared. There's no way a horse could get up and run off that fast with a rider. (00:10:55)
Continuity mistake: When Benny is looking for the black book in the office, he gets caught by O'Connell. When they are standing under the fan, you hear the scream of the Egyptologist. They all look towards the camera but when Benny runs out the window behind them, the Egyptologist is there. (01:18:40)
Continuity mistake: When Henderson shoots the burning guy to save Jonathan, I counted at least ten shots from his pistol. Also happens when Rick shoots, he seems to fire off more than the 12 shots you would think he'd be limited to.
Revealing mistake: When Evie is chained to the altar next to Anck-Su-Namun, the closeup of Anck-Su-Namun shows the bandages across her throat twitching slightly with the actress's pulse. The problem is, she hasn't been brought back to life yet.
Continuity mistake: Rick's wrist brace is missing in prison and during the trek across the desert, with no sign of the tattoo we learn in the next film is under it.
Visible crew/equipment: In the opening action-scene, as Rick backs away from the wall when the raiders start to leap over, there's a shot behind him where the camera pulls back... and you can see a near-perfect row of white markers (likely for the extras or actors) in the sand. There's at least five of them in a line.
Revealing mistake: In the first shot of the movie, the camera moves from the Sphinx through a town square. If you pay attention to the people in the crowd, it becomes painfully obvious which people are real (who were filmed in front of a green screen and composed into the scene) and which people are CGI. There's at least 4 (likely more) CGI people in the town square to populate it more, and they all noticeably move with a stiff, generic "walk-cycle" and even look slightly "blocky," like they're low-polygon models.
Visible crew/equipment: In the opening action scene, when the raiders start firing their guns towards the French Foreign Legion, there's a wide-shot of several French troops being killed, and a few of them fall over a balcony to their death. As some of the soldiers on the left side of screen fall of screen and land behind some piles of sand, you can briefly see the edge of an air bag (or some other form of padding) pop up a few times with each one. (00:09:06)
Chosen answer: The tattoos on his forehead are the Egyptian Hieroglyphs that spell "Underworld", and the ones on his cheeks are the Egyptian Hieroglyphs for the word "truth." All Medjai males get these tattoos as part of the coming-of-age rite, when they turn sixteen, of which the most important is the tattoo on their right wrist (which Rick O'Connell also has) that marks them as "warriors for God." Other tattoos specific to Medjai males are on their arms, forearms, hands, pectorals, shoulder blades and beneath the navel - the tattoos on the nose and chin are no longer used, since the time of Seti I. Medjai females only get the wrist tattoo when they come of age, but are not marked with any of the other symbols that are particular to men. Fun fact: If the Medjai - male and female alike - shows any sign of pain or cries during the tattooing process, it is considered that they have brought shame to their family.