Continuity mistake: Keep an eye on the letter that Cary Grant has with all of the names of the potential theft victims. 1) The way it is folded changes from 3 folds to 2 and from up to sideways. 2) The suite numbers are wrong , as seen when CG goes to Grace Kelly's, and it is different from the list.
Continuity mistake: Danielle is lying on the float then goes to sit up. The first lower camera shot shows her left leg bending behind her other knee. The high camera angle change shows both of her legs fully extended.
Continuity mistake: When Cary walks into the office at the restaurant of his friend there is a clipboard hanging on the wall of glass. It disappears near the last scene in the office. No one leaves with it.
Continuity mistake: At the restaurant of his friend, while in the kitchen the waiter with the silver streak in his hair sets down two bottles of wine on the coffee table and turns his body away from them. The labels are facing the office. Moments later when Cary picks up one of the bottles the label is facing into the kitchen. The bottle only has one label, as shown when it is thrown to the dishwasher and he catches it then turns the bottle.
Continuity mistake: When Cary walks into the office at the restaurant of his friend there is a brown wooden box on the desk near the lamp. When the restaurant owner comes into the office the box is silver and then changes back to a brown wooden box in the next shot.