Other mistake: When Margaret and Andrew first walk into the Immigration Office there are a group of extras seated directly to the left of them, in two rows. One of them, a guy with glasses and long black hair, wearing a white shirt with patterns (back row, second from the wall, next to the guy in the light yellow shirt), briefly looks at the camera as Margaret and Andrew walk by.
Continuity mistake: In the scene where Magaret is talking to her two bosses, when Andrew knocks at the door, the boss who is on the chair adopts two different positions while listening to her. But he can't within such short time. At first his left hand is pointing at Andrew, showing Andrew not to interfere. Then just after, you can see him on his chair with his legs crossed. Then he returns to his previous position. (00:10:10)
Continuity mistake: When Gammy enters the bedroom on the couple's last night, after separating the two lovers, she walks away and nearly disappears in the corridor. Just after, in another shot, you can see her walking away as if she was still in the doorway, although she has already walked past it. (01:20:45)
Revealing mistake: During the scene in New York City when Margaret proposes, a Boston police car is quite noticeable in the background. (Filming took place in Massachusetts, not NYC.)
Continuity mistake: At the end of the movie when Margaret is cleaning out her office, her hair has suddenly grown to the bottom of her waist. Throughout the movie it was just past her shoulders.
Continuity mistake: When Margaret answers Frank's call on their first night she bumps her bag off the chair. The bag lands on its side, the camera is then on Andrew, and when it goes back to Margaret the bag is placed neatly next to the chair.