Continuity mistake: If you look carefully at the monster (Frankenstein) you will see that his face is different in the ending scenes. The reason is, during the movie you see the monster take the woman doctor and throw her out the laboratory window. You then see the monster kind of stumble, which he really did and broke his ankle. So in the final scenes they replaced Lon Chaney Jr. as wolfman with a stuntman, and Lon Chaney Jr. finished the movie as the monster.
Factual error: After the first encounter with the Apaches, the covered wagon is headed to the Fort at full speed. The camera pans to the Apaches on the ridge and you can see a truck driving at the bottom right corner. (00:32:00)
Continuity mistake: The length of Edward G. Robinson's necktie rises and falls, often within the same scene.
Factual error: When the riders are watching the wagon train, in the background you can see a communication tower with conical speakers.
Deliberate mistake: The same scene of William Bendix at bat swinging and missing is used repeatedly in the film.
Revealing mistake: When the American pilots flying P-47 Thunderbolts are attacked by German fighters, the German planes are really American P-51 Mustangs painted with German markings.
Continuity mistake: In the scene where Judy Garland and Fred Astaire go to the nightclub to see Ann Miller, Ann invites Fred to come up and dance with her. When she is dancing by herself, she is wearing red high heels. When Fred comes up, she is wearing red flats.
Revealing mistake: When Howard and Curtin chase Dobbs, they pass a dead donkey which is obviously breathing, and the rope used to tie its legs together is visible too.
Continuity mistake: Near the end of the movie, Lucinda is severely injured in her leg, and has to hobble to walk. In the last scene (a short time later) as she approaches her home, she is walking with no problem, and has her arm in a sling.
Visible crew/equipment: During the movie whenever Bob Hope is pulled off the wagon by his team of horses you can see a board leaning against the wagon that was used to help the stunt man when he was pulled off the wagon.
Audio problem: When Phillip plays on the piano, the music doesn't match his finger movements.
Plot hole: When Ralls runs the Witch onto the reef, he is at the helm. As she strikes bow on, the wheel spins madly for no reason, as the tiller ropes would not have been affected by the collision.
Audio problem: In a scene when the Blandings first move into their dream house, Cary Grant (Jim Blandings) says something to a workman and his lips clearly don't match what is heard.
Continuity mistake: When Leona picks up her hand mirror, her medicine tray is positioned directly in front of her on her bed. When she puts the hand mirror down in the next shot, the medicine tray is pushed about a foot away from her bed.
Continuity mistake: When Montgomery Clift puts the boy into his jeep, the jeep has the standard seats. When he arrives at his house with the boy, the jeep has custom seats. The seats change again later in the movie also.
Continuity mistake: When the big dog points his gun towards the hole in the log, the length of the log changes between shots.
Continuity mistake: When Pepe Le Pew enters the house all frozen up, you can see there is nothing on the table next to the bed where the dog is, but when Pepe goes into the bed with the dog, a glass and jug have appeared.
Continuity mistake: When we see Elmer getting himself ready to go to bed at the start of the cartoon, the window he is dressing in front of does not have a frame, yet it does have one when see Elmer winding up the alarm clock in the next shot.
Continuity mistake: When Bugs is about to tee off at the first hole at the golf course, the objects behind him change position between shots.
Continuity mistake: The protagonist wakes up screaming and runs away from her cabin. A conductor restrains her. During the scene, the shadows on the wall/poster and on the torso of the black helper heavily change depending on the camera angle used. (00:02:25)