Continuity mistake: When the village crowd separates and reveals a standoff between Indy and the black-robed swordsman, the rear shot of Indy shows his hip-bag to the rear of him, the frontal shot of Indy shows his hip-bag on the forward part of his hip.
Visible crew/equipment: When Indy and Sallah are deciphering the head piece there is a shot over Indy's shoulder. As he turns you can see the reflection of a fluorescent light in his glasses. (00:48:40)
Factual error: When flying from Nepal to Egypt Indy passes over Arabia. The state of Jordan is shown, but in 1935 Jordan was called The Emirate of Transjordan.
Continuity mistake: Marion's bar in Nepal is built with thick stone walls, but after the fire, all you see is the burned-out shell of a wood-frame building.
Visible crew/equipment: When Indiana is chasing the Nazis in the truck, look closely at the convertible, you can see the camera on the windshield. (01:23:25)
Continuity mistake: When Belloq is talking to Indy and Marion in the Well of Souls, he's shown holding his hat with his right hand. But in the only over-the-shoulder shot (looking into the Well of Souls) the hat is laying on the ground and Belloq tosses a stone down with his right hand. Then the hat is back. (01:10:35)
Factual error: It should be a tricky task to put an object the size of the Ark on board a German VIIC submarine; perhaps you can find enough place inside but how do you manage to introduce that bulky case through the narrow hatches of the sub? Even the torpedo load hatches were just a little more than 21 inches in diameter.
Continuity mistake: Just after Indiana (barely) escapes the tumbling boulder at the beginning of the movie, he leaps through a veil of spider webs, only to be held up by the native hunters and Belloq, who takes the idol from Indiana. Watch carefully - there is a thick strand of webs attached to the idol as Indy hands it to Belloq, but they disappear in the next shot as Belloq hefts the idol and holds it up in the air.
Factual error: Indy's satchel is a Mk VII gas mask bag, which was created for use in World War II, so it didn't even exist at the time the film takes place (1936). The similar Mk V existed at the time, though.
Revealing mistake: Where is all the light coming from in the Well of Souls, even after the entrance was re-sealed, and the only torch still burning went out?
Continuity mistake: When Indy and the Peruvian are entering the cave and clearing the cobwebs, you can see at least one spider on Indy's back. The next shot shows a clear, long shot of Indy's back with light reflecting on his jacket and no spiders. In the next shot, the Peruvian notices the spiders. (00:04:20)
Continuity mistake: When the government comes to see Indy at the University he is teaching, they enter the large room, I think it's a gymnasium. He puts the huge book on the table and one of the buckles comes undone. But when he goes to open the book to show the g-men a picture of the Ark he undoes both buckles. (00:15:30 - 00:19:30)
Continuity mistake: At the beginning of the film, Indiana Jones uses his whip to disarm a man with a handgun. The scene showing this action includes several quick shots, but as a result of the use of these multiple shots it can be seen that the whip descends twice. (Slow motion helps, but isn't required.)
Factual error: At the beginning of the movie, when Indiana is looking for the temple, you can hear a bird call. It also can be heard when Indy is running from the natives. The bird is a willow ptarmigan. It lives in very cold areas in the far north of North America. Even a very directionally-challenged ptarmigan could not possibly end up in South America. You can also hear the unmistakable laughing sounds of the kookaburras, only found in Australia.
Factual error: The film starts in the year 1936, and just like the RPG Indy uses to threaten Belloq with, the MP40s (or at the earliest, MP38s) are an arms-historical anachronism in this movie. As the numbers in their names imply, the MP38 was first produced in 1938. The weapons in the movie are not the similar-looking ERMA MP-36, you can see the ribbed, vertically angled magazine holders typical for the MP40 - its predecessors had either a 30°-canted, smooth magazine holder (MP36) or a round viewing port for checking the ammo (MP38). (01:31:45)
Continuity mistake: In the beginning, Indy's partner takes the idol, throws down the whip, and leaves him hanging on a ledge with the ceiling closing down to the ground. While he is hanging the you can see that the ceiling barely has enough room for Indy to fit. Indy struggles to get up which during this time he would have no room to get under, yet when he finally gets up the ceiling has risen giving him plenty of room to get under. (00:08:45)
Continuity mistake: When Indy and the German driver crash through the villager's construction ladders the truck is missing the Mercedes-Benz hood ornament that appears in every other shot.
Continuity mistake: When Indy is being lowered into the map room, the exterior shot of the opening does not match the interior. From the outside, the wall around the opening is a lot thicker. The angle is also different. (00:50:55)
Revealing mistake: During the truck chase scene, Indiana is thrown or forced over the front of the bonnet and almost run over. There is a wide camera shot, and while holding on to the front fender, Indiana can be seen sitting on a chair which is attached to the truck. (01:27:40)
Continuity mistake: When Indy is climbing into the map room, he throws the staff of Ra down the hole, yet when he climbs down, it's resting perfectly against the wall, as if someone had placed it there. (00:50:40)
Answer: Indy and Marcus Brody believed that the Ark needed to be studied. They certainly didn't want to put it back where it was found. They believed that the U.S. government would find the best archaeologists, researchers, and scientists in the world to study the Ark. They are both upset that instead, the government has decided to simply lock the Ark away. This is why Indy says, "Fools. They don't know what they've got there," as he is leaving the building.
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