Factual error: When they go into the water, they put mouthpieces in, but, a few times, they talk to each other, which is impossible with mouthpieces in.
Plot hole: When Bridgette ran through the glass and Linda and Jim were at the hospital Jim tells Linda he called her mom and told her what happened and she was coming to stay over the next day. Yet apparently her mom forgot what happened because she had her committed because Linda didn't remember what happened to Bridgette's face. Also, Bridgette was like 9. How come no-one just asked her what happened?
Continuity mistake: Mr. Furlong pushes Zeke into the fishing tank and it breaks, soaking him from head to toe with water. Moments later they are walking out and he is dry.
Visible crew/equipment: When Dennis Weaver is in the cafe a shadow of a cameraman is cast across the table he is sitting at. The shot then changes to a wider angle to reveal that there isn't anyone near him who could have cast that shadow.
Revealing mistake: After King Kong destroys the train track of the oncoming train, in the POV shot directly behind the train operator while he watches Kong rise from the broken track, the small model's support control bar is visible at the right as it moves up and down. The next shot is a close-up of the shocked motorman, and after he attempts to stop the train, there's another shot facing Kong with the control bar visible for a moment. (01:31:50)
Visible crew/equipment: As Rick and Chris get in the Volkswagen Bug after Shelly returns it, you can see three crew members in the backseat window reflection. (00:35:55)
Continuity mistake: When Fin stops near the school bus, the bus number changes from "278146" to "278245" during the rescue of the kids.
Plot hole: Spoilers. It's revealed that the barn game takes place at an old farmhouse owned by the family of Jill Tuck - Jigsaw's widow. It's public knowledge that she was married to Jigsaw and that buildings they owned served as the headquarters of several past traps, so the barn should have been investigated at some point in the meantime. Ten years have passed. It makes no sense that the barn was never investigated and that the bodies of the barn victims were never discovered.
Suggested correction: The game was unknown to police even 10 years after John died. Now they've found all his other games and his multiple lairs. There would be no need to continue the search.
Hogwash. They would have definitely searched known properties associated with Kramer and his family.
I agree. In the second Saw movie, the police discover that John Kramer is Jigsaw. With this knowledge, not only would the police be able to freeze his assets but, they would be able to look into his financial records and look into any properties he owns like houses, warehouses, etc. Since the cops now have a face and a name, it's a very big plot hole why they never searched his home or any other places. If they had, more traps would have been found and confiscated.
Factual error: Lori takes a screwdriver towards her left-hand side of her abdomen. The doctor says it just missed her liver, and she has lost a lot of blood. The liver is on the right side of the body and nowhere near where she took the injury.
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)
Revealing mistake: Right after Nell sends Hugh to hell, Dr. Marrow and Theo come out of hiding behind a pillar. As Marrow puts his hand on the pillar, it squishes in as if it was made of foam rubber, instead of stone. (01:39:50)
Revealing mistake: When the UFO makes the huge flash that knocks everyone in the cemetery down, one of the police officers kicks a tombstone as he falls and it wobbles back and forth. (00:13:35)
Continuity mistake: When Blair asks Mitch "why aren't you answering me?" he says he got a weird message from Laura Barns. Blair replies "that's not funny" and Mitch replies "I'm serious." Then Blair gets a message from Laura, and when she switches back to Mitch's conversation, the last two entries, "that's not funny" and "I'm serious" have disappeared. (00:10:50 - 00:12:30)
Continuity mistake: When Norma and Helen are in the salon, and they are talking about Carrie going to the prom with Tommy, Norma is getting a fancy hairdo done for the prom. But in the next gym scene, she has her plain braids and a cap on. (00:48:20)
Suggested correction: When you watch the movie leading up to that event, it's obvious that Norma is a tomboy, and is always wearing a ball cap and wearing her hair like that. It's who she is and perhaps decided after her hair was done that it didn't feel right and decided to go back to her look.
Continuity mistake: When Michael enters the Elrods' home and steals the knife, as he picks up the knife from where Mrs. Elrod had left it, there are several drops of blood that fall onto the lunchmeat, presumably from Michael's injuries from having been shot. A few seconds later when Mrs. Elrod walks back over to the lunchmeat and reaches for the knife and sees the blood, the droplet patterns are different.
Factual error: At the climax of the movie, Alice swings the machete at Mrs. Voorhees and decapitates her. When the blade makes contact with Mrs. Voorhees' neck, her head flies off at an incorrect angle, as though the cut began on the opposite side.
Factual error: Carbon dating cannot be used without knowing the amount of C14 in the atmosphere and its evolution in history. Using this method just after arriving at an alien planet is impossible.
Revealing mistake: When Nica crawls to the elevator to escape Chucky, she bends her legs in order to shut the elevator door. She is meant to be a paraplegic and have no feeling in her legs.
Continuity mistake: In one of the last scenes, Cate Blanchett is standing in the doorway of her son's room. She is wearing a blue striped dress. When she walks into the room, she's wearing a floral dress.
Other mistake: The construction of a staircase does not require a large nail at the site shown on the steps. Furthermore when Emily snags her clothes basket on the stairs it lifts a small nail up. How did it grow into a 2 inch fat nail?
Suggested correction: Sorry to burst your bubble here but there is scuba equipment which allows for talking whilst using a regulator.
They're not wearing such equipment. In the movie they're just wearing regular mouthpieces.
In the DVD commentary the writers explain that the divers should have been wearing full face masks which allow for communication, but the director changed it for mouthpieces, but kept the talking in. They pointed out this mistake.