Revealing mistake: When the shark first attacks and bites off Jim's arm, you can briefly see his real arm under his shirt as he's screaming in pain. (00:34:10)
Factual error: Near the beginning when the boat pulls up and the guy on the boat tells the blond convict he's got a beauty 13 foot "Tiger shark" that's up in some sort of sling, the so called tiger shark is actually the same robot mako shark from the rest of the movie, just with stripes on it. Tiger sharks have a blunt rounded nose, not a pointed one like a great white. (00:07:35)
Revealing mistake: As soon as the three survivors are coming out of the lab through the hatch underwater, they all signal each other to rise to the top. Look at Saffron Burrows, her cheeks are full of air and you can almost see the surface above her head. You can also see the exact same shot when she is about to be eaten by the last shark. And what's with that hand gesture - to cut or for the shark to stop? (01:26:30 - 01:33:10)
Suggested correction: Her cheeks are like that because when we all take in a big breath of air and hold it so not to breathe, that's what happens. The hand gestures when she goes in the water is so the blood can mix with the water so the shark can smell it.
The hand gesture the entry is referring to is just before she is eaten by the shark, the actress waves her hand across her neck area, allegedly to indicate to the director that she was running out of air.
I think she is giving the shark a sign... like stop or don't attack or something like that. So I think she is giving the shark a sign because right after she does that the shark stops swimming towards her.
Maybe in the context of the film you could argue that, but for scenes in which actors are performing underwater, they use that gesture to let the director know they are running out of air.
If you look EXTREMELY closely in one shot with the girl at a close distance and the shark far away you can tell the girl is actually computer animated. So I think she is giving the shark a sign cuz right after she does that the shark stops swimming towards her. But I could be wrong... that's just what I think.
Yes, Saffron Burrows' character, Dr. Susan McAlester, used the hand gesture to lure the shark by mixing her blood in the water, rather than signalling that she was out of air. While she was holding her breath with puffy cheeks, this action demonstrated her intelligence and scientific understanding of shark behaviour. Her strategy aimed to draw the shark closer, allowing her colleagues a chance to kill it, even though it ultimately led to her tragic fate of being eaten.
Revealing mistake: At the end of the film, when Preacher is fighting the shark, we can see that it is a white stuntman doing the scene for LL Cool J. (01:28:00)
Revealing mistake: In the scene where L.L. Cool J. is in the flooded kitchen and the shark comes in through the door, he climbs up a shelf, then falls in the water, then climbs out again. Before he makes his way to the oven you can clearly see that under his pants he is wearing knee pads. (00:53:35)
Factual error: A double oven has a double or triple insulating wall between ovens, not a single sheet of flimsy steel. (00:56:00)
Factual error: Late in the film, Susan is wearing rubber aquatic shoes. She goes to her quarters to retrieve the data and decides to electrocute the shark that attacks her. She takes off her rubber wetsuit and stands on it on the metal table to insulate her from the current so she doesn't get electrocuted herself. But, isn't she already insulated by the rubber on the bottom of her shoes? Was this just a reason to get her to take her clothes off?
Continuity mistake: When the shark is brought up to put the needle in his head, it bites off Jim's arm, leaving only a bit left there, but when they are wheeling him to the helicopter you see that he's got more arm than before. (00:33:50 - 00:35:25)
Revealing mistake: In the shot when the helicopter is about to crash into the building, take a look at the blade. There is a wire holding the helicopter.
Factual error: Despite the massive size of the sharks, there's no way that the waist high water would be completely covering the shark. Right before attacks, no one sees a shark until the dorsal fin comes up out of the water.
Continuity mistake: Towards the end of the movie, the Preacher stabs the shark in its left eye with his cross, causing it to bleed. In the later scene, when shark returns to eat Susan, its eye is intact. (01:28:10 - 01:32:45)
Factual error: Since the water was always waist high, how could the huge sharks swim inside? Not to mention the corridors... (00:51:10)
Other mistake: When Carter is sitting in front of one of the small hatch-like doors around the time that they were climbing the ladder to escape from the rising water, one can clearly sea that the door is no more than twice the width of Carter (4 feet at most) yet the 45 foot shark about 10 to 12 feet wide seems to have no trouble squeezing through. (01:01:40 - 01:04:20)
Factual error: There's no way those dynamite sticks could have produced anything like the humungous explosion at the end of the film. In fact, the most they would have done would have been putting a hole in the shark's skin. (Proven on Mythbusters.)
Revealing mistake: When Samuel L. Jackson is attacked and killed by the shark, you can clearly tell that he is CGI. His arms and legs are segments and it looks really corny. (01:00:05)
Continuity mistake: The man with the cross has a wound on the left hand side of his head. Later in the movie it has moved down.
Factual error: The so-called 'tiger shark' fed to the Makos is quite unrealistic. As someone already mentioned, the snout is that of a Great White. Furthermore, the teeth are that of a Mako. Tiger shark teeth are very distinct; they resemble a cross between a dagger and a saw blade. (00:09:10)
Continuity mistake: Near the end scene, when the three characters came to the surface, L.L. Cool J. was taken by the shark. When he was taken underwater and when he surfaced, the shark had him in her mouth on the right side. When they went under again and resurfaced, L.L.Cool J. was on the left of the shark's mouth. What? Did the shark not like him on the right side so she switched him underwater? (01:27:30)
Continuity mistake: When LL Cool J is standing on the shelf and reaching for his bird on the pot, it is clear that he could easily reach the pot if he clenched his fingers. Yet, in the next clip, the pot is shown from a different angle and is at least 1 or 2 feet away. (00:53:55)
Continuity mistake: When the shark rises above water with Jan partially in its mouth, its teeth are in about the level of her waist. As Carter grabs onto Jan, it moves its teeth up to the top of her chest. In the wide shot that follows, though, its teeth are back at her waist, then in the last shot of her being pulled underwater, they are up way higher again, at her chest.
