
Continuity mistake: The stone block Indy pushes out to create an opening which allows him and Marion to escape the Well Of Souls apparently rolls down the hill outside. We see it, in a following scene, laying about 15 feet away from the Well. But when Indy is fighting the big German guard near the airplane, one scene clearly shows the Well in the background and the dislodged stone is now laying on the hill only a few feet from the opening. (01:15:45 - 01:18:10)
Continuity mistake: When Indiana is fighting the Big German mechanic by the plane, the plane goes around in circles and the wing tip of the plane punctures a hole in a petrol tanker that is parked near by. This causes the petrol to gush out of the tanker and you can see that ground underneath the plane gets totally drenched with petrol. But in the later shots, the ground under the plane is dry. There is also a shot where you can see the tanker in the background not pouring petrol any more and all you can see is a little wet spot around the tanker. (01:18:45)
Continuity mistake: When Dietrich, Gobler, and Belloq arrive next to the destroyed Flying Wing, Gobler is on the left of Dietrich and Belloq on the right. In the next shot, they have switched places. (01:20:58)
Continuity mistake: Belloq, Dietrich, and Gobler arrive next to the destroyed Flying Wing and begin to walk towards the intact wing, while Dietrich says, 'Have it put on the truck.' In the next shot, the Flying Wing and the entrance to the Well of Souls have disappeared from view (instead of the latter, you now see the hut where Pat was). In addition, some barrels suddenly appear between shots, next to which the three antagonists stop. (01:20:59)

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: When the Nazis are loading the Ark in the truck, you can spot Toht next to the left side of the truck, watching the scene. A few seconds later, he walks out of scene, apparently going to the car. However, when Belloq and Dietrich walk to the car and Belloq shouts "Let's go!", Toht has disappeared. (01:21:45)

Continuity mistake: At the beginning of the Truck Chase, when Billy Horrigan starts shooting at Indy, Reg Harding's right hand goes from grabbing the front passenger seat to grabbing the metal bar of the jeep between shots. (01:23:28)

Continuity mistake: When Indy is chasing after the truck on horseback, he jumps off the horse and onto the truck, as he does this the horse begins to slow down and fall behind, but as Indy throws the German soldier in the passenger seat out of the truck the horse has disappeared, it could not have been hidden from view behind the truck, because the horse's shadow would have been visible. (01:23:30)
Continuity mistake: When Indy is fighting the Nazis on the truck, one Nazi is thrown from the truck and is rolling the opposite direction of the truck. (01:23:30)

Continuity mistake: Several times during the fight in and around the truck the bars around the top of the cab come off and are miraculously back on again. (01:24:05)
Continuity mistake: When Indy throws Terry Leonard out of the truck, the forest they were driving through disappears. Then Indy closes the truck's door and the forest reappears. (01:24:22)
Continuity mistake: Just as Indy crashes Gobler's jeep for the second time, you can see that beside the desert road is a large forest. However, the jeep falls off a cliff that appears out of nowhere. (01:25:37)
Continuity mistake: When the camera shows the back of the truck, there are two soldiers on each side of the truck, plus the sergeant inside it. As there were seven soldiers and one of them fell off the truck - there's a missing soldier in the scene. (01:25:50)
Continuity mistake: As the Nazis are preparing to leave Tanis, a soldier fires a shot into the air, causing several Arabs to fall to the ground and land in the middle of a circle of soldiers. In the next shot, as Belloq heads for the car, all the downed Arabs, the sergeant and the circle of soldiers have disappeared, with only the soldiers who were loading the Ark onto the truck remaining. (01:26:55)

Continuity mistake: As the sergeant climbs to the truck's roof, Belloq turns his head to watch the scene. In that shot, the staff car is passing next to a group of plants. In the next shot, almost all the plants have disappeared. (01:26:55)
Continuity mistake: While Indy is fighting the German who is driving the truck, you can see that the German has got blood on his left hand, but when he throws Indy through the windscreen his left hand is clean and there is no blood on it. (01:27:10)
Continuity mistake: When the sergeant throws Indy out of the truck window, the adventurer grabs the Mercedes logo with his left hand. After two shots, he is to have let go. However, in the next shot, Indy is grabbing it again. (01:27:25)

Continuity mistake: When Indy runs over the sergeant, the background behind the truck changes between shots, going from the desert to a mountain. (01:28:45)

Continuity mistake: Indy looks at the Wurffler through the binoculars. In the next shot, when he takes them off and looks at Katanga, the submarine has moved to the left and astern. (01:34:58)

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)
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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