Continuity mistake: The Angel of Death, judging from the position of the lid of the Ark (the two angels can be seen below the ghost), is located just above Dietrich's head. However, Toht screams as if it were right in front of him and Dietrich as if it were in front of Belloq (judging by their looks).
Continuity mistake: In the shot after Belloq's death, the generator and the rock Indy and Marion are on have disappeared.
Continuity mistake: As Dietrich and Gobler come into the tent, Toht's leather case can be seen already opened. In the next shot, the case is suddenly closed.
Continuity mistake: While the Holy Fire is killing the soldiers, in a shot of two soldiers being hit by the light, the stone wall is missing in the background of the scene. (01:47:30)
Continuity mistake: When Marion arrives on the deck of the Bantu Wind, Dietrich turns to look at her. Katanga is in the background, behind the colonel. But, just before Marion hits Dietrich, Katanga appears on the opposite side from where he was and catches Marion. (01:36:00)
Continuity mistake: When the gunfight at The Raven begins, the Ratty Nepalese crawls next to two tables (one of them has the medallion and the log). He knocks down the one without the medallion, but in the next shot, the knocked down is the one that has the log and the medallion. (00:31:10)
Continuity mistake: Eaton and Musgrove are sitting, waiting for Indy to open the book. When Indy opens it, suddenly Musgrove is standing. (00:19:43)
Continuity mistake: When Indy abruptly brakes the truck and the Ark box slides backwards, the poles on either side of the box have disappeared.
Continuity mistake: During the procession, there are four soldiers carrying banners. When they arrived at the Altar, one has disappeared.
Continuity mistake: During the procession, after Indy hides behind the box, Captain Mohler can be seen walking with the soldiers behind the Ark. In the next shot, he's walking in front of the Ark.
Continuity mistake: In the first scene of the procession, the Nazis are walking in a straight line along a path. In the next shot, they are now going around a curve.
Continuity mistake: When Marion gets off the submarine, there are two soldiers behind her. In the next shot, one of the soldiers has disappeared.
Continuity mistake: When the Wurffler arrives to Geheimhaven dock, six soldiers and an officer are running towards the submarine. In the next shot, the seven men have disappeared.
Continuity mistake: On the blackboard, between the numbers 4 and 5, the word "and" is written. After the girl shows the "Love you", the word is replaced by a dot. (00:13:49)
Continuity mistake: Over Belloq's left shoulder and behind Toht, a soldier stands next to a klieg with a machine gun. In the next shot, the soldier's gun has disappeared. (01:44:25)
Continuity mistake: During the procession scene, in the shot before Toht takes off his hat, about twenty soldiers can be seen walking. After Indy leaves the procession and hides behind a box, in the next shot, there appear to be twice as many soldiers as in the first scene. Just before Indy shouts "Hello!", the quantity has returned to twenty.
Continuity mistake: After the kliegs behind Dietrich, Belloq, and Toht explode, the Ark energy begins to destroy the soldiers' guns and the kliegs next to them (including Indy and Marion's). In some shots, the kliegs on the altar are still working.
Continuity mistake: When the two soldiers place the Ark on the altar, they move to the walls of the canyon, and Toht stands next to Belloq. A few shots later, the soldiers are next to the Ark's poles (where they will be in the next shot), and Toht seems to be very huge. (01:44:39)
Continuity mistake: As the Ark is placed on the altar, Toht moves to the left of Belloq. Behind the German, a soldier without cap can be seen filming with a hand-held camera. In the next shot, that soldier has moved to the opposite side of the canyon and is squatting. (01:44:24)
Continuity mistake: Just before Belloq says "It's beautiful!", there is a black machine (which is not the German camera or the generator) in the bottom middle of the screen, just below the approaching ghost. It is also visible when the Angel of Death is revealed. This machine disappears when the Ark begins to kill the soldiers.
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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