Continuity mistake: During the conversation between Joe and Harry, Meg Ryan's head position is inconsistent between angles, sometimes just for a subtle tilt, other times more conspicuously. For instance, when the two guys are entertaining awkward laughter before Joe introduces Sally to Harry, she looks in opposite directions. (00:15:25)
Continuity mistake: On the plane, the guy sitting next to Sally decides to be a bro to Harry hitting on her and switches places. A stewardess behind them vanishes in thin air as the shot changes. The two stewardesses keep disappearing / changing position throughout the scene. (00:18:15)
Factual error: When Harry meets Sally for the second time it is on a flight in 1982. But the plane is a second-generation Boeing 737-300, the first of which entered service in December 1984. (00:21:00)
Continuity mistake: When the three women are talking in the open air restaurant, just after Meg broke up with her boyfriend, check the background scenery. It alternates between very cloudy, sunny, and dim and bright, even though the time passed is only seconds. (00:23:25)
Continuity mistake: Over lunch, Sally tells her two friends that she broke up with Joe. Meg Ryan's hair is conspicuously in front of her shoulders in the close-up but behind her shoulders in the wider angle. (00:23:50)
Continuity mistake: When Marie is going through potential available dates to pitch to Sally, look at Carrie Fisher's wrist, in particular when she mentions the second name, "Ken Darman"; the hands of her watch point to a different time practically every shot. (00:24:55)
Factual error: Marie spots Harry poorly hidden in the "personal growth" section of the bookstore. The scene is supposed to take place in 1987, but there are books both next to him ("Sex and Morality; Who Is Teaching Our Sex Standards") and to the girls ("Making Life Right When It Feels All Wrong") that were published mid-1988 and couldn't be there. (00:29:25)
Other mistake: Sally phones Harry while he is staring at a dipping bird. She tells him that Casablanca is on TV, and he specifically asks for the channel. "Channel 11," she says. When she says "Last scene" later, you can see on the display of Harry's TV set that he's tuned to channel 07. (00:35:30 - 00:37:40)
Continuity mistake: Harry is blowing off some steam with his friend, practicing swings. When he says, "Why can't you give me credit for this?" look at Bruno Kirby; his baseball bat switches hands, but he is still holding it with both hands and repeats the movement in the next shot. (00:43:35)
Continuity mistake: When Sally is faking her orgasm, the slice of meat on her sandwich changes the way it's folded over the bun between angles. (00:45:10)
Continuity mistake: In the scene where Harry and Sally are having lunch in the diner (the orgasm scene), Harry's napkin is in his lap. You can see it when the camera angle is from the side showing both of them from the knees up. Every time that angle is used, the napkin is in a different place or altogether gone. (00:46:00)
Continuity mistake: In the deli scene when Sally is faking her orgasm, the camera movies to Harry. You can see the waiter approaching. When the scene is over, the waiter again approaches to take the order from the other woman (Rob Reiner's mom). (00:46:25)
Revealing mistake: Look at Harry and Sally carrying the Christmas tree together. Then jump towards the end of the movie when Sally is dragging on her own a tree for the next holidays. Each garland and even the fake snow covers on the sills are the exact same one year later, down to each crease. At least the vendor changed jackets. (00:48:35 - 01:21:50)
Continuity mistake: During the dinner scene in the restaurant, Marie puts down her glass of cola on the table. In the next shot, she is drinking from the glass again. (00:53:50)
Continuity mistake: Once Harry met his ex and her current partner, Sally in the view from behind moves her arm behind his - the movement can be easily spotted because of the lyrics sheet she is holding. But in the next shot, she asks him if he's OK, and a few seconds later, she is repeating that same movement. (00:59:15)
Continuity mistake: When they are playing win, lose, or draw, Sally is trying to draw baby talk, and if you keep your eye on the drawing the baby looks different all the time and has eyes, and then doesn't have eyes, etc. (01:04:15)
Revealing mistake: In the scene where they have just had sex, Meg goes to get out of the bed and is supposed to be naked, but when she puts on the bathrobe you can see she is wearing some type of slip or nylon panties. (01:11:20)
Continuity mistake: After their first time having sex, Sally gets up to go get some water. When she comes back, she gets back in bed with Harry and settles herself with her head laying on his left pectoral. There is a quick change of shot, and suddenly her head is much higher, with her head laying on his left shoulder. (01:12:30)
Continuity mistake: The interior scene on the airplane shows a 707, with the lights mounted on distinctive boxes underneath the overhead bins. The airplane shown landing is a 737, which had the interior lights mounted flush.
Factual error: In the classic Katz's' Deli scene Rob Reiner's mother tells the waiter 'I'll have what she's having'. One problem - Katz's is a cafeteria-style delicatessen; there are no waiters that come to the tables in the section where she's sitting.
Answer: Sally could be upset for having to drive Amanda's boyfriend, or it could be awkward because they don't know how to say goodbye. There could be a number of reasons why things appear tense between Sally and Amanda, just not explained.
That was a big question mark for me as well when I watched the movie, to the point that I had to re-watch the beginning because I was sure I had missed something; their behaviour doesn't make sense.
Sammo ★