Continuity mistake: When the shark is attacking the catamarans with the teenagers aboard, in one shot you see Andy fall backwards, still on the catamaran, and he is barefoot. He is then knocked in the water, and when his friends pull him back out of the water on, he now has white trainers on. (01:20:10 - 01:21:15)
Visible crew/equipment: When the shark is coming towards Mike as his friends are trying to pull him out of the water, in the shot when the camera is on the shark's back, there is a large crew boat behind one of the sailboats, visible in the top right corner of screen. (01:22:00)
Revealing mistake: There's one bit where we see the shark slamming into a boat and gliding along the side with its mouth open. Not only does the shark's latex mouth bend beneath the snout, narrowing from pressure, but within the mouth you can clearly see yellow hydraulic tanks to open the mouth. (01:22:05)
Continuity mistake: When Brody is out looking for the teenagers on the police boat, he is shown approaching the lighthouse while passing a buoy on the left of screen. When we see Brody and the police boat from behind the top of the lighthouse, there is no buoy anywhere. (01:23:55)
Continuity mistake: The pilot in the rescue helicopter wears no sunglasses as he is about the take off. But when the shark is attacking the copter, sunglasses briefly appear on the pilots face in one shot, then vanish. (01:28:15)
Visible crew/equipment: After Chief Brody rams the police boat into Cable Junction, in the behind shot, shadows of the camera and crew members are reflected on the stern of the boat below the word police. (01:40:40)
Revealing mistake: When the shark attacks the catamaran remains which only Jackie and Sean are on, as the shark hits, one of it's front top teeth is clearly bent in half. It remains back to intact in all other following shots. (01:44:30)
Continuity mistake: Brody has a hold of the large power line, and the shark is gliding along straight for it. In all the shots of Brody holding the power line, the green jacket he wears has wet splashes on it. One patch of water on his right shoulder briefly disappears for one shot, the reappears in the following. (01:46:45)
Visible crew/equipment: In the scene where Brody approaches the group of teenagers on their smashed boats, the angle cuts to show Brody approaching seen as if from Cable Junction. At this point, there is a huge mistake. The teenagers' boats are clearly visible in the foreground, the kids have all completely vanished, and you can spot the cameraman standing on the boats quite clearly.
Continuity mistake: When the kids are drifting around, a heavy rain shower comes. Seconds later, in the shot of Sean on the upside-down sail boat, you see reflections of sunlight and a large part of the boat he is sitting on is completely dry.
Continuity mistake: When Brody and his wife are driving towards the harbour just after the diving accident, the sky is overcast. When they get to the harbour the skies are clear. When they sail away in the police boat the sky is overcast again.
Audio problem: When the helicopter lands and the teenagers cheer you can hear dialogue from later in the film in the background. Several times you hear "Sean, catch the rope." which they yell later in the movie.
Continuity mistake: In the scene when Chief Brody, his wife & deputy come across the sail boat named "Tina's Joy", they find Tina in it, and during this scene Chief Brody's jacket is placed on Tina's shoulders. The Chief then leaves the sailboat in search of the other teens. Later scenes show the Chief wearing this jacket when in fact he left it with Tina.
Continuity mistake: At the end of the movie when the Chief has killed the shark, you see his son Shawn cheering, with his hair completely wet and messed. By the time the Chief paddles over, Shawn's hair is now perfect; dry, and combed neatly...
Audio problem: When the shark breaks the katamaran and most of the teens fall into the water by Cable Junction, one of the girls can be heard screaming in the underwater shot of the shark. That is perhaps fine, but the sound of someone screaming as heard under water continues over a few clips from above the surface.
Factual error: The "Cable Junction" in the movie is a transformer junction station built on a rock pile however when you look at it there is no algae or barnacles anywhere on the rocks. This is impossible because algae and barnacles thrive on rocks in sea water.
Continuity mistake: When Brody is out looking for the kids, and he sees Mike's boat approach - the sky in the background is overcast. When they meet, the sky is clear.
Continuity mistake: In the close-up scenes at Cable Junction, with water, the sky is clear. But in the scene where Brody is climbing on to the cable, the sky in the background is completely gray - and actually looks like a studio wall.
Continuity mistake: In the scene where Brody drives his jeep onto the ferry he drives it to the edge. Yet in the next shot when it reaches the other side the jeep is about two feet from the edge.
Revealing mistake: When the divers are snorkeling underwater for lobsters and they find one and try to grab it the lobster they show is a southern lobster without any claws. Lobster from New England look very different from the one in the movie and have claws.
