The second model to enter for the fashion show is wearing a top with red spots (possibly strawberries) and a red skirt. After the cut she's wearing a top with red and blue stripes and a white skirt.
When Mary is reading in bed, the early long shots show the lamp on the left side of the bed to be a male figurine, and the one on the right to be a female. In the close-ups, the lamp on the left of the bed has changed and is female.
When Mary is on the phone with Stephen during the lunch party, she puts a cigarette in her mouth and strikes a match, lighting it, the cigarette doesn't light, and she holds the unlit thing through the rest of the conversation. When they cut to long shot of her hanging up the phone, the cigarette is smoking, and she stabs it out in an ashtray.
When Crystal is taking her bath she smokes a cigarette, which she eventually throws away. However when Little Mary enters the bathroom, Crystal is again smoking and we never see her lighting this other cigarette.
In the train's club car, the countess's hand jumps from holding the stem of her champagne glass to being folded in front of her between shots.
The legend and publicity of this film is that it's all about men though none appear. But, at the lunch party when the ladies are looking at Mary's picture in a magazine, Douglas Fairbanks Jr. is clearly visible on the back cover. (Incidentally, the ex-husband of co-star Joan Crawford.)
Two years passes between Mary's divorce and her subsequent reconciliation with her husband, but little Mary, her daughter, doesn't seem to grow at all during that time.
While Lucy is leading Sylvia away after her fight with Miriam it is clearly a stunt girl that is doing the leading. She doesn't get her face behind Sylvia's head quick enough.
When Little Mary says, "Sheba, get off of Daddy's coat," to her dog, her lips close before the line is finished.
When Princess Mara says hello to Mary, an odd male-sounding voice responds "hello" from no apparent source. None of the women's mouths are moving.
Barn doors for a sound stage light appear to be hanging from the 'ceiling' in Mrs. Haines' living room. It is visible during Mary's conversation with her guests from the moment where Peggy helps her put on a necklace, up until they leave the room.
As Lucy hauls Sylvia into the house after her fight with Miriam, the camera (after panning from left to right, following them) quickly jerks back before the film cuts away, indicating that had the camera panned over any further, the set would have been revealed.
At the Reno ranch, Countess DeLave exclaims "I've always put my faith in love. Still... I have had four divorces." However, earlier on the train, she had explained that her first husband left her a widow (and left her all his money) and she had only divorced the following three.