Revealing mistake: After the report on the Kia, Sean receives a call from the Warfield police department. Sean is a professor in Connecticut, but his mobile carrier as shown in the close-up of the phone is Rogers, a Canadian company. The film was shot in Ontario. (00:39:50)
Revealing mistake: The protagonist broadcasts the description of Emily's car in her vlog. She then receives a mail from a mom in Michigan...or does she? Seems not, because if you look at the window of the mail open in Safari, she is on the Compose tab, not in the Inbox, with a Send message and format and style buttons at the bottom (and she is not replying to the message because the 'from' field is a "michiganmom381" gmail account. (00:39:20)
Factual error: Detective Summerville tells Sean that his wife got a rental Kia from Budget paying in cash. But Budget does not allow the initial cost to be paid in cash; the payment must come from credit or debit card, cash can be used only as the last payment when you return the car. (00:37:30)
Continuity mistake: When Stephanie sets the bottle in the wine cooler as the detective arrives, the label with the name of the wine in italics faces the camera. When she walks off and when the detective looks at the table with the close-up, the back label is the one facing the camera. (00:37:00)
Other mistake: Bashir Salahuddin appears in the ending credits of the Italian localization as "Detective Summervile" with one L. It's a spelling mistake that appears also on IMDB, so one wonders if the localization team lifted name from the website, or if the theatrical version had the spelling mistake and was fixed afterwards.
Continuity mistake: At the beginning of the scene inside the Dennis Nylon mansion, Emily is wearing her bag on the left shoulder. She sneaks her way inside the "employees only" area, loses her cover (the guy bringing clothes upstairs), still with the bag looking the same, but the moment she enters Emily's office in a rush, she is wearing her bag across the chest, right shoulder strap, bag on the left side. (00:34:00)
Continuity mistake: Inside Emily's office upstairs, Stephanie ducks under the desk when someone walks by. The floor is fully in the dark, and yet when she crawls to the drawers she tries to pick the lock of, there are distinct sunlit areas all of a sudden. (00:34:15)
Continuity mistake: Dennis Nylon partially undoes the knot of Stephanie's scarf, which is then for the rest of the scene adjusted in a more aesthetically pleasing way (less straight and flat) despite the fact that neither he nor she had a chance to do so. (00:32:45)
Continuity mistake: The protagonist just approached Dennis Nylon; he asks her about the vintage scarf. Seen from behind, Stephanie's left hand is on the strap of the bag, but in the reverse angle her hand is down. (00:32:35)
Continuity mistake: After the talk with the police, Sean says he should call a cab and go home. His hand goes from below to the counter, to above it. Likewise, Stephanie checks her watch without and then with her elbow leaning on it. (00:29:00)
Continuity mistake: For the first time at Emily's, Stephanie stops befuddled by the "beaver." When she says "Lifelike", Emily has her blonde hair over both shoulders, but in the next two close-ups there's none on her right shoulder, and then a few locks. It happens again at the end of that part of the scene when she walks away saying "No such luck" about the painting having any value. (00:07:05)
Continuity mistake: Stephanie and Emily are talking in front of the school. Behind Emily, the same person with a red raincoat and pink-red umbrella passes by twice, and when Stephanie says "I think you're joking, but great!" a girl with a red raincoat pops in the view of the door but is nowhere to be found in the next shot. (00:06:10)
Continuity mistake: The first time we see Emily, Stephanie is looking at her open the car door and make her way across the street. Even in slo-mo, it takes a few seconds. But before AND after the sequence, the same dad with a plaid shirt and dark jacket is coming out of the school. (00:04:40)
Continuity mistake: When the teacher asks to the class "Haven't we learned so much about food all over the world?" there's a blonde kid behind her who reaches for a crayon off-screen, then is prominently featured in the cutaway shot where she is drawing already on the paper with it, and then we're back to the same angle as before where she is -still - waiting for that crayon. (00:03:15)
Continuity mistake: The bloodstain on Sean's shirt is different between the close-up when Stephanie checks on him and when he stands again. (01:45:50)
Continuity mistake: In the opening shots of the funeral, Stephanie is holding her son's hand in the first, and his shoulder in the second. (00:41:25)
Continuity mistake: Sean hands the "vegetable smoothie" to Stephanie holding it by the middle, which becomes the top in the reverse shot. (00:30:00)
Continuity mistake: When Linda Cardellini says "beatific" to the protagonist, her knife points the sharp edge in the opposite direction of the previous and following shot. (01:11:40)
Continuity mistake: Outside during the funeral reception, Sean and Steph are dealing with Nicky. The camera cuts to the parents of the kid's classmates gawking at the scene, but before and after they can be seen in background through the window minding their own business and chatting oblivious to what happens outside. (00:43:30)
Other mistake: Emily does not let people take her pictures, but she obviously has documents - she signed papers and has a driving license - and also has a husband quite fond of her who spends ages sucking face with her. With all that considered, nobody picks up on the obvious fact that her mole (which is in a position that would show in every mugshot) switched sides.
