Continuity mistake: Mary's glass of wine goes from being almost empty to about half full during her conversation with Charlotte. In the same scene Charlotte goes to put the bottle down but in the next shot she is still holding it.
Continuity mistake: In the scene where the F.B.I. storm Dick's house, Charlotte's sleeves change length (i.e. being pulled up or like normal) throughout the entire scene. (00:20:00 - 00:20:30)
Other mistake: In the scene where Don arrives at Dick's 'party', he looks at his non-existent watch. (00:13:25)