Factual error: Mick's hat has genuine crocodile teeth set into the hat band. It would be confiscated and destroyed by US Customs on his arrival in the USA.
Factual error: The "whaling boat" is too small to function as such. It isn't large enough to hold a fin, let alone disassemble a humpback whale.
Factual error: When Steve Martin dies with the mask on, the inflation bulbs (the little black bags that inflate and deflate) deflate completely. Actually they should INFLATE completely and stay that way. The gas is still on full blast and Steve is no longer inhaling (which would cause them to deflate). It was done only to emphasize Steve Martin's demise but it's factually incorrect.
Factual error: Calendar date at the very beginning of the film (in the police station), shows the dates of Saturday 20th/Sunday 21st July 1983. However the 20th and 21st July 1983 fell on Wednesday and Thursday.
Factual error: When the first robot is trapped in the lift, the teenagers shoot the propane tanks on top of the lift in order to get them to catch fire and explode, killing the robot. However the teens are firing pistols or shotguns, and these do not contain incendiary ammunition, which is what is required to make the propane to catch fire.
Factual error: The movie they're watching in the theater, "The Fly", is shown backwards. The first scene they see should have happened after the last scene they see.
Factual error: When Ack Ack is collecting shells on the beach for his father, he's really collecting shell casings... which should be where the guns are fired, not where the explosions are.
Factual error: During the speedboat chase scene, the Toronto skyline is visible, including the CN Tower. This movie is supposed to take place in an American city.
Factual error: Cameron tries to stop Ferris from borrowing his father's red sports car, explaining that it's an extremely rare and valuable '61 Ferrari 250 GT California. But the car itself is not a real Ferrari. It was manufactured by Modena Design and Development of El Cajon, California, and is a "Modena GT250" which strongly resembles the 1961 Ferrari 250 GT California Spyder. Since the film makers were throwing the car out of a window, using a real Ferrari was 'cost-prohibitive'. Comparing the real Ferrari to the Modena, differences include the Modena's sharper body crease above the grille, the more steeply angled headlamp covers, higher-mounted emblem and counter-sunk hood scoop.
Factual error: In an early scene, the high school science teacher produces a schematic diagram of the two nuclear bomb designs created by the Manhattan Project. He says, "Here are two designs based on plutonium." Actually, only the Fat Man bomb uses plutonium. The other, the Little Boy design, uses uranium.
Factual error: When Jack meets the prostitute at the corner there is a car parked the wrong way in a one-way street. (00:17:50)
Factual error: Barbara befriends her kidnappers in her joy over losing 20 pounds while she was with them. Leaving aside that she's been with them no more than two weeks, and it's near impossible to lose 20 pounds in that short amount of time even if you literally starved yourself; she also most definitely would have noticed a weight loss that big. On a frame as small as hers, she would have noticed big differences in her body's shape and feel, and none of her clothes would have fit. (01:00:00)
Factual error: After escaping from the back of a NYPD cruiser that apprehended her at the British Consulate, Terry runs into the NYC 57th Street N/R line subway station. In the very next shot, she is running past Cole's French Dip Restaurant on 6th Street.in Los Angeles. The restaurant sign even mentions its location.
Factual error: Charlie's 58 Impala is a sweet ride, but his license plates don't have the requisite year stickers. His car has the '56 series of plates, and each subsequent year would require that current year's sticker.
Factual error: When Number 5 is watching Saturday Night Fever, he is watching and grooving to the climactic dance-off scene in Saturday Night Fever on TV. Stephanie then enters and the scene on TV shifts to one much earlier in the movie he's supposedly watching. (00:57:15 - 00:59:30)
Factual error: Spence says that Claudia is Italian, but the very efficient butler greets her with "Buenos dias", and according to Ellen she was a big Chilean film star. Nothing strange that Ted Danson would be wrong about her nationality like he often is wrong about names, but in the end credits we have a similar Spanish/Italian language mixup with an "Italian director" listed, when the person in the movie finale speaks Spanish. (01:25:00)
Factual error: There are profound problems with the geography of the U.K. In the beginning, Stimpson is at a train station. He wants the Norwich train, but instead gets on a train bound for Plymouth. There is no station where you could get a train to both. Plymouth is in the South West. To get there from London, you go out of Paddington. Norwich is in East Anglia and you get there from Liverpool Street.
Factual error: The brothers had a two-way mirror installed in the fitting room. Todd makes faces at his brother through the glass. If the mirror had really been two-way, the woman would have seen the reflection of Todd making the faces and would have known something was up. (00:19:28)
Factual error: Tuba pranks the store manager while he is reading adult magazines. One of them though (the one he is holding) is the August 1985 issue with Angela Nicholas on the cover. The previous scene took place at the Hong Kong Marathon of 1985, in January.
Factual error: In the scene when Walter was in the den in the middle of the floor, Anna lifts up part of the blanket and he falls through to the first floor. However, in the next scene, he appears to be able to walk without any problem. The second floor was at least 20-30 feet above the first floor and was covered with all sorts of rubble and a wooden floor. If he had fallen that far, he would have been badly injured and would not have been able to just walk like he did.