Visible crew/equipment: After Indy and Henry have escaped from Castle Brunwald, Indy jumps into one of the boats, pulls the motor starter cord and jumps back out, then just as he bends over to release the boat from the piling, right between Indy's legs the black covered arm of a hidden crew member appears from under the tarp taking hold of the throttle, steering the boat away from the pier. (01:02:40)
Factual error: At the end of the film Rainwood has established his innocence of the drug charges and is happily back at work as a senior mechanic for a large airline. However, part of the sentencing and plea bargain protocols at his arraignment is his previous conviction on a lesser drug charge years before. It goes without saying that he did not advise his employers of this when he started work for them - no airline in the world (even pre 9/11) would hire someone with a drug conviction on their record! Now this is out in the open the airline knows that Rainwood is a convicted drug user (on the lesser, legitimate charge) and that he lied on his original job application. They wouldn't hire him again to sweep the floors.
Plot hole: R.J. Fletcher is shown as a ruthless businessman who knows everything there is to know about Channel 62 - who owns it, how much it's worth, who is running it, the financial troubles it is having and so on and so on. He is also fully aware of the telethon and the fact that George is selling the station as a going concern for a total of $75,000.00. It is simply asking too much of audience credulity or 'suspension of belief' to think that such a hard-headed businessman would not work out that he could, using stooges, buy a controlling interest in the station for $37,501.00, saving himself a small fortune and closing the station down over the objections of his minority shareholders. Something this blatant could not possibly be a character mistake - he is already planning on buying the station for the full price (from Big Louis) so don't tell me he wouldn't just switch plans and buy it from George instead!
Continuity mistake: When Carlotta brings the plates for the meal they all have a dome cover with a top handle, but when Sebastian runs across the table those handles have changed. (00:54:50)
Other mistake: Beethoven didn't seem fussed nor resentful of Napoleon being part of the group. Historically he temporarily admired him and wrote the Third Symphony inspired by Napoleon's ideals of Europe's new hope of enlightenment but later despised him after he crowned himself Emperor of France in 1804 and furiously scribbled out his name off the title page of his Third Symphony and named it Eroica which he originally titled it as "Bonaparte Symphony" due to his former admiration of Napoleon.
Other mistake: Spock lifts his crew mates with the rocket boots. He passes deck numbers 35 through 78 from bottom to top. First off, deck numbers go from top to bottom. The bridge is on deck 1. Second, the Enterprise of that class only had 23 decks.
Character mistake: The sign for the hotel where Jake is staying at in Mexico says Tengo Quarto's para Renta. The word is spelled wrong. It should say CUARTOS. Also, there is no apostrophe s in cuartos. It is plural, not possessive.
Continuity mistake: In the bowling alley, 'Pal' comes over to speak to Tia. During their conversation, the camera pans to Maisie throwing a bowling ball; however Tia is now sitting alone. Pal has disappeared. (00:40:10)
Audio problem: In the scene where Leo explains how he launders the drug money and Roger says "You're a cheat", Leo says "Come on, everyone cheats a little, look at the pentagon." But when he says "look at the pentagon", it's dubbed in because the sound of his voice doesn't match his other dialogue, and if you read his lips it doesn't match either.
Visible crew/equipment: When Billy is in the van telling the Wolf story, a microphone is visible behind Henry's left arm.
Revealing mistake: When Louis is trying to get Gage off him near the end of the movie, as he's struggling in a few shots you can plainly see it's not really Gage but a dummy made to look like him. Looks like a doll. (01:33:35)
Continuity mistake: When the Joker's henchmen are trashing the museum, one guy puts red handprints all over a portrait, later the Joker walks by the same portrait and the handprints are gone. (00:59:55)
Other mistake: Dr Anne wets her dress by dropping water on it, but her dress is dry afterwards. (00:54:00 - 00:55:30)
Factual error: The film takes place in a private boarding school the 1950's, however one of the students is studying from a 1980's chemistry textbook. The obvious giveaway is that the spine of one book shows HBJ as the publisher. Jovanovich was not added to Harcourt Brace until the 1970s.
Factual error: Joe Jackson batted left-handed in real life, not right-handed as Ray Liotta portrayed. He also threw right-handed and not left-handed like it shows when Kevin Costner is hitting him fly balls to left field.
Revealing mistake: When the 54th Mass. marches past a liberated plantation some black children wave them on. One of them is wearing a digital wristwatch.
Continuity mistake: When chasing Jamie in the woods, Mikey's headlights go from normal chevy headlights to off-road high beams.
Continuity mistake: Notice Marty's hair in the scene when he's playing "Johnny B. Goode." It's quite larger than when he says, some seconds later, "I guess that you're not ready for it yet." That's because when he says that, it's a recycled shot from the original BTTF, whereas most shots showing he's playing the guitar are newly made for BTTF2. However, Marty's hair is considerably longer in the new shots. (01:27:19)
Factual error: In the scene where Clark is working on the lights the full moon is shown. This is December 14th according to the advent calendar. On December 24th when Santa's sleigh goes sailing over the moon, it is still full.
Factual error: Budapest didn't exist in 1489. The cities of Buda and Pest weren't combined until 1873.
Suggested correction: Even today in 2023 felony convictions might not show up on a background check. Not all information has been uploaded to the internet yet. It was extremely easy in the 1980's for a conviction to be missed by a background check especially if there was no prison time served or it occurred in a rural county or town.
He just got out of prison and establishing his innocence involved the violent deaths of at least two people. Do you not think that his employers just might have followed his story? He'd be all over the news media. The idea that not one person would have followed up on his criminal history is beyond absurd - we are talking about a safety critical job that involves the safety of hundreds of people.