Continuity mistake: When Jeannie is on the settee talking on the telephone, the cord is missing in some shots.
Other mistake: Leonard Nimoy is incorrectly mentioned in the credits as 'Leonard Nemoy'.
Plot hole: Jean Simmons is supposed to actually be correct about her husband being in love with his sister in law, and not insane. When she enters the nightclub acting weird, in a dress too large for her and hanging off her, exposing her brassiere, she is completely out of character. She is not drugged at this point, as she stopped drinking the paraldehyde before this.
Factual error: The movie's title "The Inn Of The Sixth Happiness" is the name of the mission station that Gladys Aylward/Ingrid Bergman sets up. In reality this was called "The Inn Of The Eighth Happiness." Numerology is popular in China, where eight is regarded as a particularly auspicious number. Apparently the film company thought "sixth" had a better ring to it than "eighth." In the movie it is explained that there are six levels of happiness. This is not a Chinese belief and seems to have been invented for the movie.
Other mistake: Outlaws are chased by a mounted posse. One outlaw up on a hill shoots two of the posse members from long distance. Next shot, the two injured posse members are lying on stretchers and the chief deputy orders someone to go back to town and get a wagon. The stretchers were canvas, wooden handled, military style. Where did they come from?
Continuity mistake: The sheriff's wagon the 30-foot man picks up is a 1958 Plymouth. But the car that is rolling after he drops it lands on the ground is a 1950s Chevrolet. When the sheriff tries to call for help, the smashed car is the 1958 Plymouth again.
Continuity mistake: When Diestl and Hardenburg attempt their wild dash to the coast on the motorcycle, they pass the same wrecked Kubelwagen three times.
Continuity mistake: When King Arthur says "A good idea, fool!", Bugs Bunny stops and you can see that behind him is a wall. In the next shot, Bugs is now in front of King's Arthur's chair, and when he says "Beheaded?" he is back in front of the wall again.
Continuity mistake: When Daffy rushes up to take his breakfast from Elmer, you can see the door behind them is closed, but when Elmer tells Daffy he's had enough, the door is now open.