Continuity mistake: Satipo drops the whip half a meter away from the closing gate, then runs away. However, when Indy rolls underneath the door, the whip is laying right next to it.
Continuity mistake: When Indiana is hiding his face with the cloth, watch as he enters the tent that Marion is being held prisoner in - at first, Indiana has to hold it in place; in the next shot, he has it tucked into the rest of the folds. The next shot, the actual position of the cloth changes.
Revealing mistake: The Pan American aeroplane Indiana Jones boards in San Fransisco looks similar to (but has noticeable differences from) the Boeing 314 PanAm used for transpacific flights. This aeroplane did however not fly until 1938 and at the time of the story the company only flew transpacific with Sikorsky S-42s, an aeroplane with a completely different body than the one used in the scene.
Revealing mistake: When Indy is fighting the big German at the base of the airplane, Indy reaches down and grabs a handful of sand to throw in his face. You can see the finger marks in the sand from a previous take.
Audio problem: When Marion meets up with Indy on the steps of the building at the very end of the film, she asks what was going on in there. Her first few lines of dialogue were dubbed in after shooting. Her mouth isn't moving with the dialogue.
Factual error: Several times during the movie, Indy is under fire from Nazis or other bad guys wielding what look like MP-38 sub machine guns. The movie is set in 1936, 2 years before the weapon was even designed. The Erma EMP-36 has wooden parts (the grip), the muzzle spike at under the barrel is more pointy and the front sight are more massive than MP-38/40, and the magazine is tilting slightly forwards towards the muzzle. The MP-38/40 is all stamped sheet metal (no wood, because it would slow down production), the muzzle spike under the barrel is more smooth (maybe so it won't get stuck?) and the front sight is more simple (basically just a ring with rumble strips) than the ERMA's, and the magazine on the MP-38/40 is vertical.
Continuity mistake: After Indy replaces the idol for a bag filled with sand, the position of the bag changes between frames.
Other mistake: During the truck scene, after the German soldier hanging onto the door falls down and another guy crawls over the roof, palm trees are reflected on the windshield, but wide shots show not a single tree around because the palm trees area was left behind a while ago.
Continuity mistake: In the map room, after Indy has discovered where to put the stick in, the sun rays lights the head and shoulder of a painted figure and the whole body of the figure to the right of it. A frame later the first figure is now completely lit. Too fast a change.
Continuity mistake: When Belloq talks to Indy in the Well of Souls the two Arabs on the left disappear in the angles from Indy's POV.
Audio problem: When Toht walks in with Dietrich and Gobler, watch the background, you will see Dietrich's lips moving, but you cannot hear him saying anything.
Other mistake: At the beginning of movie when Indy is about to steal the gold idol, the camera does a close-up of it. The idol has been in a decaying temple for hundreds of years. but it appears shiny and new, as though just placed there. You'd expect the idol to at least be dusty or covered in jungle debris.
Continuity mistake: Indy climbs on a plane's wing, and a German mechanic arrives and asks him what he's doing, raising his left arm and ordering him to approach. A shot later, the arm is down.
Continuity mistake: When Indy and Brody meet at the University with the two government officials, a group of rolled maps or plans are placed on a podium horizontally. Halfway through the scene, they are all laying vertically.
Other mistake: When Indy and Marion are sealed in the well of souls, they are completely cut off from the outside world. As such, other than the torches, it should be pitch black, but it is surprisingly well lit in there.
Continuity mistake: After the plane takes off in the beginning, Indy sees the snake. His hands are grabbing at it, but a second later his hands are on the rim of his cockpit.
Continuity mistake: When Indy is driving the truck with the ark, a German tries to get in on the right side. Indy kicks the door open twice, and after the second time the top hinge of the door gives easily. The guy is half way dragging on the ground, holding onto the now askew door. Then in the next closeup, the door is hung correctly with the guy on it, and Indy kicks it again. The guy goes dragging again, and then he and the door fall off.
Continuity mistake: There is a shot during the truck chase scene where a Nazi falls out from the back of the truck and goes through the windshield of the car behind it. During the shot from inside the truck, we see two Nazis to the left. The one closer to the camera pushes the other one down. However, in the very next shot, we see that pushed-down Nazi immediately sitting up straight.
Continuity mistake: From the outside, the sides of the hole to access the map room are in shadows, from the angle inside they are sunny.
Continuity mistake: During the truck chase scene, the radiator bars Indy hangs onto keep swapping back and forth from bent outwards to slightly bent with no continuity at all.
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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