Continuity mistake: In the beginning of the movie, Sarah and Tom are at the airport returning from their honeymoon. While walking through the airport, Tom pushes Sarah and she gets coffee spilled on her shirt. Later, when she approaches Tom in the parking lot for a ride home, the coffee stain has suddenly disappeared from her shirt in this shot.
Revealing mistake: When Sarah is leaning over Tom to speak to Yuan on the intercom at the McNerney gate, Yuan is looking at the monitor in the kitchen. The monitor shows the car and there is a person wearing a white shirt sitting in the passenger seat of Tom's car. It can't be Sarah, who was sitting in the passenger seat, but now is leaning over Tom in the driver's seat, plus she is wearing a red coat.
Continuity mistake: After coming back from the honeymoon, Tom, having two reddish bruises on his cheeks, walks into KNR Radio for his 2 AM stint and chats with Fred. However, after recalling all the memories, Tom walks out of KNR Radio a few hours later and speaks with Kyle, but the reddish bruises are no longer there.
Revealing mistake: In the scene where Tom accidentally kills Sarah's dog, he is seen reading a magazine while struggling with the dog. The dog continues to gnaw at Tom's ankle, and eventually rips open his snap pants. In a couple of the shots, you can see an ankle brace that Ashton Kutcher wore to protect him from the dog's bites.
Factual error: In the scene where Tom and Sarah are in the French castle, there's a flag hanging in the background. This is the official flag of the Austrian province of Tyrol although the whole scene plays in France.
Continuity mistake: After Tom sees Peter kissing Sarah, when she enters the room he accuses her of wanting Peter. Seen behind Tom is his blue backpack and part of his red sweatshirt on the same chair as Wendy's red bra. There's a close-up of the chair when Sarah spots the bra and it's seen again when she picks up the bra. The red sweatshirt is positioned differently in each of these shots.
Continuity mistake: In the scene when Tom and Sarah both have tissue up their noses, the position, size and length of Tom's tissue changes throughout the whole scene.
Continuity mistake: When Sarah and Peter pull up to Peter's friends' house in Italy, Peter gets out of the car. Inside the car, you can see the middle bit where the champagne was and in the seat next to it, you can see there is nothing or no one there. That is where Sarah is supposed to be sitting. But in the next shot you see Sarah just starting to get out of the car, which means you should have been able to see her.
Continuity mistake: When Kyle is sleeping on the couch, in the wide shots from upstairs and downstairs the golf bag is behind his right shoulder. In the close-ups the golf clubs are behind his left shoulder. The sandwich, paper towel, mustard bottle, lamp behind couch also change in these shots.
Revealing mistake: When Sarah walks into an artist and subsequently falls, she brushes up against the fresh canvas on the easel and falls into the wet paint brush he is holding in his hand. The paint is supposedly wet on this painted canvas and paint brush, as the artist is seen with his brush applying paint to this painting. If this were the case, then the paint would have smeared onto her, the red coat or her purse when she brushed up against it as she was falling or when she was on the ground, which is seen on the screen.
Continuity mistake: As Sarah starts to walk on the foot bridge, on her right there are artists and their easels, canvases, etc. In the following wide shots, close-up, pan down to the Hotel Gianna and pan up from the water, the position and existence of canvases, easels, sketch box, etc. changes throughout these shots.
Continuity mistake: At the Hotel DuReve, the bellboy is in the room with Tom and Sarah. As Tom asks about Satellite TV, the white lace pillow is lying on the bed and Tom's right red draw string is caught up by his shoulder under his jacket. In their next close-up, Tom's red hood, jacket, zipper and red draw string are different, as is the white lace pillow which is now upright.
Continuity mistake: Tom and Sarah are on the plane returning from their honeymoon, and in the close-up when Tom tries to sit down you can see in the background two overhead compartments closed. However, in the full view of the compartment those overheads are now open. No one closed them between shots.
Continuity mistake: Tom throws the snowball at the blue car, it hits the rear windshield and flies off to the side as the car stops short. The snowball does not leave any snow on the windshield, however in the next shot as the blue car backs up, there's snow on the rear windshield now. Then in the next two close-ups of the blue car the snow's gone from the rear windshield again.
Continuity mistake: In the scene were Tom and Sarah are standing beside their car which is stuck in the snow, Tom throws a snowball at a passing blue car. The driver then reverses into their yellow compact, which is pushed easily over the cliff. You can see that there is very little snow covering their yellow car, as opposed to the shots right before it.