When Father Barry (Karl Malden) gets hit in the head with a beer can, he gets a cut on his forehead, which bleeds visibly in the scene. In subsequent scenes, there is no sign of the cut or of a bandage to show that he had been hurt.
As Terry walks to the pier after the climactic fight with Johnny Friendly, the blood on his forehead and the side of his face disappears.
After Johnny Friendly is shoved in the river, when he reappears exhorting the dockworkers to obey him and not to follow Terry Malloy and Father Barry, Lee J. Cobb's clothes are dry and he is well groomed again in spite of the brawl & the dunking in river water.
In the final scene, the large ship at the dock in the background changes between a freighter and a cruise ship.
Towards the end of the film when Terry confronts Johnny Friendly at the little club house on the river, a Coke machine on the porch appears and disappears between cuts.
Terry and Edie on the rooftop, a pigeon is identified as a dominant male yet lays an egg.
(The egg-laying business was clearly a joke by Terry to amuse Edie).
(The egg-laying business was clearly a joke by Terry to amuse Edie).
In the beginning of the movie in the first bar scene after Terry has set-up Joey Doyle, when 'Skins', the man from 'Greenpoint', is asked by Johnny Friendly if he "handled the sheet metal", Skins says, "yes, it was easy, here's 45 Bills" (meaning $4,500.). Friendly gives the money to Terry's brother, Charlie the Gent', to count. After he does Charlie erroneously tell Friendly the total is $2673.00, i.e., the amount 'Big Mac' says is the total of Friendly's cut from the day's shape-up of the 813 Union members that worked that day, instead of $4500.
As the scene in which Terry coaxes Edie into walking home with him dissolves, Eva Marie Saint breaks character by abruptly stopping and turning around to head back towards the crew area near the camera.
Obvious dummy being thrown off the roof in the opening scene.
In the bar in the beginning of the film, there is a television mounted on the wall. The 'screen' has wrinkles in it, indicating that it is not an actual television but a lightweight prop.
The prosecutor at the hearings is shown on TV facing Terry in the witness stand, but in the hearing room there is no television camera located behind the stand, where it would have to have been for the angle shown in the TV picture to be possible.
When Terry sets up Joey Doyle it's already dark outside, but when the camera pans up to the roof where the killers are waiting, the sky is still light.
After Terry puts on Edie's glove it still fits her perfectly. You can see as they're talking and walking their hands are about the same size. If Terry was actually a boxer his hands would be a lot bigger.
Despite being told by Johnny Friendly to put Terry in an easy job, Big Mac makes him scramble for a work medallion on the ground. And even though he gives it to Edie who gives it to her dad so he can work, Terry still winds up in the easy job sitting on the bag of coffee beans.
In the opening scene, when Joe talks to Terry, Joe's mouth doesn't match what he is saying.
When Johnny Friendly talks to the ship owner at the top of the gang plank near the end of the film, the make-up person can be seen wiping Truck's face.
In the church scene when the meeting is broken up by the thugs outside there is a long shot with the characters trying to decide which way to run and you can see a boom mic bouncing around for a few seconds at the top of the screen.
In front of Johnny Friendly's Bar at the beginning of the film, the boom mic is visible on Charley's coat as he leaves the frame.
Several times, Father Barry (Karl Malden) puts a cigarette in his mouth, but he never is shown lighting or smoking them.