Continuity mistake: Hooper wears rimless eyeglasses, with the arms either attached at the upper corners of the lenses or at the sides of the lenses. If this didn't happen between shots within the same scenes, it could be presumed that Hooper has two different pairs of glasses and switches between the two, but they do indeed change between shots, such as when Mrs. Kintner slaps Brody, or even later, on the Orca. (00:36:05)
Continuity mistake: Quint embeds his machete into the wood at the side of the boat, but in the following wideshot the machete is gone. Then as Orca starts to move, when Hooper says, "He's chasing us, I don't believe it," the machete is back. But when the shark leaps onto the boat the machete is gone again, and then as the shark devours Quint the machete is back for him to grab, so he can valiantly stab the shark. (01:44:30)
Continuity mistake: When Hooper gets his gear from below, after the explosion in the engine room, he runs to the deck passing Quint using the fire extinguisher. The camera pans from Brody, who stands on the bridge deck, to Hooper right below him. So where exactly is the tall iron ladder that leads up to the bridge deck in this shot? It should be behind Hooper, in front of the window, but it's gone. Don't fret, it's back in the following shots. (01:49:05)
Continuity mistake: At the scene just after the fake shark scare, the real shark shows up at the pond area of the beach. As the lifeguard in a small boat reacts to everyone's panic, the shark tips over the boat then appears underneath him to tear his leg off. We watch as it sinks slowly to the bottom. You can plainly see that the lifeguard is barefoot in the boat. The severed leg has a tennis shoe on. (01:02:15)
Continuity mistake: Orca's ID number normally reads MS 15 LF on both her port and starboard side at the bow. However, after Quint shouts, "Hooper, you idiot. Ain't you watchin it?" Orca's ID number reads M 15 L at starboard side and 15 LF at port. (01:16:30)
Continuity mistake: When Chief Brody is standing on the boat, almost ankle deep in water, he throws down the pump and is about to climb up the ladder. In the next shot, while he is on the ladder, the shark (we presume) hits the boat making it list to the right and the deck is dry. (01:44:30)
Continuity mistake: The number of barrels on the deck of the Orca changes from shot to shot, during the final scenes at sea. (01:41:00)
Continuity mistake: When the shark bursts into Orca's cabin and tries to attack Brody, in the shots facing the shark, at the right of the screen is the forward window. The previously shattered glass (from the yellow barrel) is now perfectly intact within the window frame, and the large wood cabinet below that window is gone. The glass is shattered once again, when Brody climbs out of the cabin, through the window beside it. (01:57:55)
Continuity mistake: After Hooper enters the shark cage, Brody takes Hooper's eyeglasses and places the left earpiece in his mouth, but when Hooper tells them to try and keep the shark off him till he's lowered, it's the right earpiece that's in Brody's mouth. (01:52:20)
Continuity mistake: At the harbor, just as Brody asks, "Help me get those guys out of the boat, will you?" in the wideshot there are five men standing on the dock and three standing in the boat. Then in the next close-up, there are four on the dock and four in the boat. The one in a black/white check shirt is now at the end of the dock and the one in a black rain slicker, that was standing on the dock, is now suddenly standing in the boat below, at its stern. (00:28:45)
Continuity mistake: During Quint's attack, as the shark's biting down on his legs, Quint's bare hand is grabbing the shark's snout. Subsequent shots show Quint wearing gloves as he's devoured. (01:57:35)
Continuity mistake: Before Alex's attack, the guy who plays with his dog Pippet on the beach wears a bright yellow Izod polo shirt with straight hemmed sleeves, in all of his close-ups. However, in all of the wideshots the polo he wears is pale yellow, with shorter sleeves that have the classic rib-knit sleeve openings. (00:14:10)
Continuity mistake: When Quint goes below deck to get the machete, with the intent to cut the barrel lines, the machete he takes is shiny and clean, with no rust or pit marks at all. Yet, when Quint holds it over his head and then embeds it into the side of the boat, the entire blade is rusty and full of pit marks. (01:44:40)
Continuity mistake: When Brody is throwing chum in water and Quint is in the chair they show him wearing no socks and old tennis shoes. After Brody falls and then sets a new chum marker Quint has brown socks on and loafer type shoes. (01:12:45 - 01:14:00)
Continuity mistake: Throughout the film, Hooper wears on his left ring finger a gold ring with a distinctive design and a small black stone. When Hooper is lowered in the shark cage, underwater the ring design differs and the stone is a much larger oval shape. (01:53:05)
Continuity mistake: Quint slams the machete into the wood beside the side cleat, and rigging lines. However, when the shark joins them aboard the boat and Quint is sliding towards its mouth, the machete's position changes - it is farther down towards the stern, note the black anti-slip mats. (01:44:30 - 01:57:00)
Continuity mistake: The damage to the bars of the cage and the top canister changes, and is quite different once Quint and Brody hoist it up. (01:55:05)
Continuity mistake: At the beach party, when Cassidy and Chrissie make eyes at each other, in the close-up he sits behind certain people including a girl with blond braids and guy in a denim shirt, with long sleeves. However, in the next wide shot, denim shirt guy has his sleeves rolled up and many of their positions are different. (00:02:00)
Continuity mistake: When Hooper climbs into the cage he is not wearing fins, yet when he is lowered in the cage, in the very first shot underwater, he is wearing fins. In the following shots he is not wearing fins, but after the shark destroys the cage and he swims to the bottom of the ocean, he is wearing fins once again. (01:52:40)
Continuity mistake: When Brody waits to board the ferry he says, "Charlie, take me over to those kids, will ya," and there's a painted board with 'Amity' attached to the ferry base. However, when they reach the other ferry landing the board with 'Amity' is gone, in sloshing water (even more visible in a deleted scene). It's the same side of the ferry, note the ferry Captain is stationed at the permanent helm at only one side. The short haul Chappy Ferry On Time scow was the stand-in for the fictitious Amity ferry. (00:11:40)
Chosen answer: As mentioned in the movie, the posion was in the needle and the shark's hide was too tough for the needle to penetrate. Hooper had to go in the water so that he could get the needle into the shark's mouth, where the flesh was less tough.
Kevin Howard