Factual error: I work for a television channel in 'daytime serial' production and I can assure you that no actor is going to secure a recurring speaking role in a soap opera unless a comprehensive insurance policy has been secured. (This applies to feature films, too.) This will inevitably involve a medical examination. I'm afraid Mr Dorsey's plans are going to become dreadfully unstuck the minute he drops his y-fronts in the doctor's surgery. (No, he can't find a compliant or bribeable doctor - the insurance company will always use their own people.).
Continuity mistake: When Marty chases after Biff on the borrowed 'skateboard', Marty is wearing a dark grey belt and a red/blue print shirt under his red/beige jacket. However, when Marty is hanging on to the front of Biff's car as they turn a corner (and in another shot), Marty (stunt double) is wearing a light brown belt and solid tan shirt. (01:07:00)
Character mistake: When Missy is at her audition, Courtney and Whitney get annoyed and tell her to do a sequence, (front handspring stepout, roundoff back handspring stepout, roundoff back handspring, full twisting layout). However, when Missy starts the sequence, she starts with a cartwheel instead of a front handspring.
Factual error: The story is set in 1976. "Funkytown" is used in the movie and the end titles. The song was not released until 1980.
Revealing mistake: When Claude and Ray are at the retirement home getting ready for bed, as Ray lifts up his shirt you will see where it looks like he's wearing a fat suit underneath. He can also be seen pulling it down to his waist.
Factual error: The movie takes place during the 1990s, but throughout the movie cars are shown with Illinois license plates with "Illinois" written in cursive. These plates were not introduced until 2001. (00:24:45)
Factual error: When the B-52 is flying low over Russia, the shadow on the ground is a Boeing B-17G, a World War II propeller driven bomber.
Continuity mistake: When the WABAC machine is going through the time vortex, trying to escape from the black hole, some tiles get sucked off the WABAC, but in the next shot they are back on.
Factual error: In the movie, we see the Statue of Liberty with its current bluish-green color. The statue only got that color over time, and as it was still being built, it should be its original brown.
Continuity mistake: As the hand creature busts the shackles off Boris' legs in Lunar Max, you can see the bottoms of his pants over his metal prison boots. There are only a few folds and wrinkles over his left foot, and the pants over right foot are hardly wrinkled at all, or affected as the creature climbs up his right leg. But only a couple of seconds later, we see another shot of Boris' feet as the creature breaks off the metal sleeve of his arm, and suddenly his pants legs are very wrinkled. Boris was standing perfectly still the entire time. Boris' legs are also suddenly closer together. (00:03:35)
Other mistake: Near the start of the movie Jon indicates that he has titanium in his right arm, but towards the end of the movie the bullet ricochets off his left arm. (00:08:55 - 01:34:45)
Visible crew/equipment: Near the end, when Rodmilla and her daughters are requested to appear before King Francis, in the first shot facing the king and queen, there is a beige narrow mat in front of the large patterned rug, which is not in previous or following shots, specifically used for crew/camera tracking (fullscreen version). (01:50:30)
Continuity mistake: In the scene where John is peeing off Stifler's balcony, he knocks over a plant and knocks out Christy. In the next shot the plant is back, and in the one after that it is gone again. (00:17:15)
Continuity mistake: The morning after Vivian's first night at the hotel, room service brings breakfast. When she's eating a croissant it cuts to a shot of Edward, and when it cuts back to Vivian she's eating a pancake which goes from being half done, to being a whole pancake again. (00:30:55)
Revealing mistake: Gracie hugs the Russian waitress in order to have a better view of the disc hand-off appear on the monitor. As she raises her left hand that holds the book/camera lens, we see that the digital feed that appears on the monitor stays steady and level, even though she is raising the book/camera lens higher and closer to her face. Obviously the feed that we see on the monitor is not taken from the book/camera lens. (00:04:10)
Continuity mistake: The chutes that Wednesday and Pugsley use changes positions when Fester chases Wednesday.
Other mistake: Even though it is snowing throughout much of the movie, none of the snow seems to stick to any of the characters' fur. Even during the fight scene when they are rolling around in it, they are never covered with white.
Visible crew/equipment: When a gremlin attacks the Mum from a Christmas tree, and the tree falls on top of her, you can clearly see a member of the crew with eyeglasses, wearing a red shirt, standing behind the tree pushing it forward on top of her. (00:54:30)
Continuity mistake: During the scenes at her Mother's house, Kate's hair goes from blonde to REALLY blonde.
Factual error: When the barracks are completely flooded, Eggsy uses his bare fist to punch through a large two-way mirror to escape. The fact is that any glass (or plexiglas) thick enough to contain hundreds (or thousands) of tons of water without bursting would be as impenetrable as concrete to Eggsy's bare fist. He would need a chisel-tipped jackhammer to penetrate such a mirror.