On the train, the men with the shotguns shoot out the glass of the same window several times.
The position of Tom's tie changes from when he first kneels at the wedding and in the following cut.
For some reason, Joel McCrea's hair is parted on the right side in the beginning of the movie and changes sides when he arrives in Palm Beach to meet his wife.
When John finally introduces himself to Gerry, he is holding his book up, but in the next cut it is in his lap.
Gerry's hand changes position when hiding in the closet from the Wienie King.
Gerry (Claudette Colbert) is referred to as "tall," "dark-haired," and "long-legged." She is in fact short, blonde, and rather shorter-than-average of leg.
In the Zodiac Club the soundtrack is of muted trumpets while the actors are clearly playing open horns.
During the shootout on the train, the cracker bowl is knocked over. The rod used to knock it over is visible.