Factual error: When Indy and his father are being chased by the German soldiers on motorbikes they can be easily identified as modern lightweight Japanese trailbikes, not the big heavy bikes the German army used. (01:03:35)
Continuity mistake: Inside the zeppelin when Indy and his father are talking at the table, notice the white handkerchief that moves all around the table. (01:13:50)
Revealing mistake: Indy and Henry go through a tunnel to avoid the Nazi planes, but one flies into the tunnel anyway. When it goes into the tunnel, it's covered with matte lines, and it's the wrong color.
Revealing mistake: Just a small detail. Watch the tank roll over the hill with the German officer holding onto the top. When the tank hits the ground, the turret pops off. The German soldier (a clear prop dummy) maintains its grasp on the turret and is pulled off with it. The sheer force of the crash would have easily blown a human body off the tank. (01:36:30)
Factual error: When Indy is being chased by the tank there is a type 82 Kübelwagen - they weren't produced until 1940 and the movie is set in 1938.
Visible crew/equipment: When Young Indy is trapped in the train car with the lion, he tosses up the whip to Fedora, and as he's being pulled up in the interior shot, he's wearing a stunt apparatus around his waist above his beaded belt. [The stunt double is also wearing a glove on his right hand holding what looks like skewered meat, to presumably draw the trained lion, but that's a lot harder to see without pausing]. (00:08:35)
Continuity mistake: In the speedboat scene where Dr Schneider rescues Indy and Kazim from the boat that is chopped up by the propeller of a ship, she driving the speedboat with the steering wheel on the right-hand side. Seconds later as she drives the speedboat away, the steering wheel is on the left-hand side, obviously a flipped shot. When the speedboat slows down to allow Kazim to alight at the jetty, Indy is at the wheel which is now back on the right-hand side. (00:39:55)
Visible crew/equipment: After the Venice boat chase scene, in the shot which takes place on the boat while it is being chopped up by the propeller, look at the top of the boat (opposite where Indy is holding Kazim.) You can see a series of round-shaped set lights reflecting in the boat. (00:39:30)
Continuity mistake: When Indy is trying to hold Elsa and keep her from falling and she's trying to reach the Grail, you can see her hand coming out of her glove. In the first shot of her hand coming out, it comes almost all the way out. In the next two shots, her hand is about halfway out, then it slips out and she falls. (01:57:00)
Revealing mistake: When Donovan takes a drink from the false grail, he turns toward the camera and you can see the screw holding the base to the stem of the cup. (01:52:15)
Continuity mistake: In the beginning, when Indy is fighting aboard the Coronado ship, the very first time we see Indy in this scene (before we see him get punched), he is bleeding from the right side of his mouth. Throughout the remainder of the scene, he is bleeding from the left side of his mouth. (00:11:50)
Continuity mistake: When Sean Connery drops his lighter while trying to burn the ropes, the lid is flipped to the right. When he blows on it the lid then changes position slightly relative to the pattern on the rug, then when the rug catches fire the lid's suddenly flipped completely to the left. (00:56:40)
Continuity mistake: During the boat chase/fight in Venice, the rear of Indy's boat gets shot up and starts smoking and spouting flames and the engine starts chopping. He leaps onto the pursuing boat, fights until that boat is destroyed in the rotors, then leaps with the Grail protector back onto his original boat with Elsa. The boat is now running perfectly. (00:38:50 - 00:39:55)
Continuity mistake: In the motorcycle chase scene after the escape from Brunwald castle, Indy's hair is noticeably longer than it was in the castle scenes. It returns to the shorter length when they stop at the crossroads.
Continuity mistake: After Indiana and the Protector of the Grail escape the boat being chewed up, and the Protector reveals who he is to Indiana, watch his chest area... When Indiana asks "Who are you?" he is looking down at his chest (looking at the tattoo), and when we cut to Kazim you can tell he is holding his shirt open showing Indy the tattoo. Then when we cut to Indy and back to Kazim, his shirt is closed and he then opens it to show Indy the tattoo. (00:40:15)
Factual error: As Indiana Jones opens the door to Dr. Jones' house, note the light switches just inside the front door. They are the kind developed in the late 1970s and still in use today, not consistent with the film's setting of 1938. (00:22:30)
Factual error: German Fighters shown in the film are in fact Pilatus P-2 (Swiss-made aircraft built after World War II). The appropriate fighter of the period would be the Messerschmitt 109. (01:17:00)
Revealing mistake: When Indy is looking out at the gorge in front of him after spelling out God's name, there's a shot where he looks at the lion's head above him. You can see him from down the corridor, and you can notice as he touches the wall, it moves, showing it is a fake wall. (01:47:15)
Continuity mistake: In the beginning of the boat chase two bullets hit the windscreen of Indy's boat. In the next shot the location of the holes has changed.
Continuity mistake: When the zeppelin is shown turning around, the biplane that the Joneses are about to escape in is nowhere to be seen. (01:16:10)
Answer: The implication is that disaster would follow them outside of the cave as well. It wouldn't make much sense if you could simply outrun the disaster.
BaconIsMyBFF
"Followed by disaster" is a kind of curse, a thing not common in Christianity. It doesn't make much sense anyhow. A seal is just a dot - OK, so let's at least grant that the seal represents a circle that the grail has to stay in. Who decided where those borders are? The grail was taken there during the first crusade. That was closer to 1938 than it was to 33 AD. The three knights could move the grail about then. Why not afterwards? The knights could have built the traps. But the borders could only have been set by god, in an unusually late and completely atypical miracle.
Spiny Norman
There are several examples of curses in the Christian Bible: Lot's wife is turned into a pillar of salt for looking back at Sodom, the plagues visited upon Egypt, Adam and Eve are cursed for eating fruit from the tree of knowledge, etc. The knights did not move the grail around after finding it, they stayed in the temple for 150 years and then two left leaving the third behind. The great seal and it's restriction was already in place when the knights got there.
BaconIsMyBFF
Where in the movie is that stated? I interpreted the knight's story as them having made that place. Looks like it isn't actually specified. But if God made it, then I submit that he would have used Greek, not Latin, for the stepping stones. (All of those curses are from the old testament. The book where god kills firstborn children as long as they're Egyptian. Grail is by definition new testament where you turn the other cheek. There simply are no curses in the gospel, that's just not how Jesus rolled).
Spiny Norman
The tests were made by the knights, but the seal had God's power in it. Just like the cup.
lionhead
It's still a bit dodgy. What if you take a shovel and dig yourself a back door? Basically this film really excels at stuff that makes no sense but helps the storytelling, or to be precise, creates dramatic effects.
Spiny Norman
Every fictional story is like that in some way. That's why it's called fictional. It's just a story.
lionhead
Not a particularly convincing argument, "stuff happens for no reason all the time", if I may say so. Why is this website even here then? The fact is that some stories are more coherent than others. (♫ "In olden days, a hole in the plot, would seem to matter, quite a lot. Now heaven knows, anything goes..." ♫);).
Spiny Norman
It's the difference in what story they want told. Is it a fairy tale or based on actual events? A huge difference in plausibility between the two. The site is there to look at mistakes, not how believable the story is.
lionhead
It is not set in another universe so plausibility isn't somehow suspended. Maybe take a look at the categories recognised by this website. Plot holes, factual errors, even stupidity. (They? Who are they?).
Spiny Norman
It is set in a fictional universe because it's not a true story. With "they" I mean the writers/director. Mistakes in a plot (plot holes) have nothing to do with how believable the story is. As long as it's plausible, it's not a mistake.
lionhead
Pretty sure it's the same universe, just with some added characters/events. What about the total lack of spaceships or orcs or talking animals for example? The seal business is not a mistake YET, but it's very dodgy because no-one knows how it works or why. Like all Indys "trapped" secret places, it's (among other things) unclear who resets the traps for the next visitor. We can't brush it ALL off as "the hand of god" every time.
Spiny Norman
Huge amounts of stuff in films isn't exhaustively explained. Doesn't mean there isn't an explanation that's perfectly believable. There's zero evidence either way to say how "followed by disaster" would manifest, and just because there's not a thorough explanation doesn't mean that it's "dodgy", and it's not worth bickering about either, because there's no concrete answer either way.
Jon Sandys ★
OK but I would like to note that not everyone who offers creative explanations has recently seen the movie; some people just invent their own. E.g. "followed by disaster" is not an actual explanation from the movie, it was just one of the suggestions made here and only here. Or the ones on my own question below. All I'm saying is, it's very hard to tell what the "rules" / "logic" of this place are supposed to be, so I understand what the OP was driving at.
Spiny Norman