
Continuity mistake: In the submarine dock of Geheimhaven, Captain Mohler is a man with dark hair in his mid or late thirties. But during the procession, he seems to be much older, with grey hair.

Continuity mistake: As the ghosts dance around Dietrich, Belloq, and Toht, the Frenchman slowly looks up as the column of mist ascends upwards from the Ark, almost looking straight ahead. In the next shot, Belloq is looking down again; the shape of the mist has changed, and the column of mist is now moving to the right.

Continuity mistake: As the ghosts dance around the pole to which Indy and Marion are tied, large clouds can be seen in the sky behind them. However, after a ghost circles Dietrich and passes in front of the camera, it can be seen in the background that the clouds behind Indy and Marion have disappeared.

Continuity mistake: The distance between Otto and the Nepalese changes between shots, just as Toht begins saying "Surely he told you..."

Continuity mistake: In the Bantu Wind, the right arm of the soldier standing next to where Indy is hiding changes its position twice during Katanga's and Dietrich's speech. (01:36:18)

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: While the Ark is killing the soldiers, the cameraman is hit twice, as the first hit is shown in the first wide shot of the dying soldiers and the second when the camera focuses on the cameraman. Also, during the second hit, a beam passes through the camera and strikes the cameraman in the face, although he remains standing. In the next shot, the cameraman's body is suddenly on the ground and the beam that had killed him disappears.

Continuity mistake: When the Nazis board the Bantu Wind, there are some shots of the pipe Indy is hiding in. During these shots, there's a big grey pipe right behind Indy's pipe. However, in the rest of the Bantu Wind shots, this grey pipe is on the left of Indy's pipe, not directly behind it. (01:36:19 - 01:37:05)

Continuity mistake: In Geheimhaven, Indy watches the submarine hidden behind some ropes. When Marion comes out of the submarine and the camera focuses on the back of Indy's head, the ropes disappear. (01:39:13)

Visible crew/equipment: When Indiana frees Marion, locked in the cabin pilot of the Nazi plane just after one of the soldiers is killed by the blades, a set light is reflected on the plane's glass. (01:20:32)

Continuity mistake: As the truck pulls up next to the Command Tent, four soldiers lift the Ark's box and a fifth soldier, positioned between the two wooden posts of the Ark's box and to Gobler's right, picks up the sticks that Indy and Sallah had used. In the next shot, that soldier is now to the left of Gobler and the Ark's box. (01:21:40)

Continuity mistake: After Toht's command, the Mongolian and the Nepalese grab Marion, then the former puts his hand on Marion's cheek. During this, the Nepalese faces Marion, whose mouth is open. In the next shot, the Nepalese is suddenly looking at Toht, Marion's mouth is suddenly closed, and the position of the Mongolian's head has changed. (00:30:28)

Continuity mistake: On the Bantu Wind, after Dietrich takes Marion from Katanga and begins to leave, the soldier next to the pipe where Indy hides throws his cigarette and leaves the scene. In the next shot, when Belloq stops Dietrich, the soldier is now back at his original position. (01:36:51)

Visible crew/equipment: As the bad guys are leaving the dig site for Cairo, there is a shot of the black vehicle (lead car) looking right at the driver. On the bottom of the shot is a shadow of film equipment that shouldn't be there. The shot lingers, so the shadow is very visible. (01:22:50)

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: In the shot after Belloq's death, the generator and the rock Indy and Marion are on disappear.

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: 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: 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, 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.
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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