Continuity mistake: When we see Carol writing the thankyou note, the page is numbered (23), there are 8 lines of writing on the page and she says she is on the last page. When she is looking up the word 'conscience' in the dictionary, the paper is visible again but it is a different sheet - there is no number and there are only 4 lines of writing. It is the page she is about to write on because the last words written are 'have it on my ' - 'conscience' following this phrase makes sense. (01:09:00)
Continuity mistake: When Melvin and Frank are talking about taking Simon to Baltimore the flowers on the table are yellow and red. When Carol is reading her note to Melvin, they're orange and purple. The colour isn't off because Carol's top looks the same as before. (01:16:00 - 01:17:30)
Continuity mistake: In the scene where the three of them are driving to Baltimore, Carol has a zit on her face. In the next shot it is gone. (01:26:20 - 01:27:30)
Continuity mistake: Carol drives the Saab convertible to Baltimore, and she expresses to pull over the car, the rooftop is down. When Carol actually pulls over the Saab the car has the roof on. (01:26:40)
Continuity mistake: After the trio's arrival in Baltimore, Carol is in her room placing a call home. When she is first pictured placing the call she has a pager clipped to her jeans. It is gone, never to reappear, in the next shot. (01:30:40)
Continuity mistake: In the restaurant scene with Melvin and Carol, when she is taking her drink from the bar to their table with the help of a waiter, when she first picks up her drink there is very little in it, but when she takes the drink from the waiter and places it on the table it is practically full. (01:33:25)
Continuity mistake: When Melvin and Carol enter the restaurant on their trip, a certain song is playing (I can't recall the song). Melvin leaves to buy a jacket, returns, and just after they are seated, you hear the female band leader say, "Here's a special song for...", and it's the same song they played 10 minutes ago. (01:34:00 - 01:38:15)
Continuity mistake: After Melvin orders crabs his tie knot keeps changing back and forth between the striped and the checkered pattern of his tie. (01:35:20)
Continuity mistake: Before Carol takes a bath she tries to help Simon out of his shirt. In spite of being handicapped by his cast he insists on doing it by himself, although with difficulties, but he would never have managed to get out of his black pants into his jammie shorts between shots. (01:41:40)
Continuity mistake: In Simon's sketch, Carol is lying the opposite way to the way she is really lying. (01:49:00)
Continuity mistake: In the scene where Simon is sketching/drawing Carol, he rips off the hand piece of his cast so he can move his hand freely. When they are getting out of the car once they get home, you can see that the hand piece of cast that Simon ripped off is back on his hand and the cast is undamaged. (01:49:30 - 01:54:40)
Continuity mistake: When Carol apologizes to Melvin over the phone her watch rotates around the wrist while she is holding the receiver. (01:56:05)
Continuity mistake: When we see Melvin's bedroom, when Simon is looking for the dog, the shelf above his bed is half filled with books and bottles of water. By the end of the phonecall with Carol, the shelf is completely filled. (01:58:15 - 02:01:20)
Continuity mistake: In the end when Melvin and Carol are kissing, his arm is around her neck. This arm changes from one arm to the other in a split second. (02:12:25)
Continuity mistake: When Melvin is making a phone call outside the Mobil station, the price on the sign above the phone booth is $1.13/gallon. As Carol comes out of the station, the sign behind her shows $1.14/gallon. When the car pulls away from the station, it is back to $1.13/gallon.
Continuity mistake: Simon's cut on his lip is quite visible in the car on the trip down to Baltimore and on the way back to New York, but it miraculously disappears while they are staying in the hotel in Baltimore.
Continuity mistake: When Carol and Melvin are talking in her restaurant and he is trying to convince her to go to Baltimore, she folds up her thank-you letter, but the subsequent shots show the many-paged letter is still open in her hand in the lower left of the screen.
Continuity mistake: When Carol and Melvin are in the restaurant in Baltimore, she is mad at him and he tells her to sit down. When the camera is on her, her hand is on her hip but when the camera cuts to Melvin, her arm is down over her stomach or in some other position during the scene.
Continuity mistake: After Simon has to dismiss his housekeeper, she is leaving the apartment with her large purse in one hand and several carrier bags in the other. She then lifts her hand, which is now empty, and says, "But who's going to walk Verdell?" There was no time for her to shift or drop her purse.
Continuity mistake: When Carol enters Melvin's building soaking wet to tell him she'll never sleep with him, we can see bra straps across her back under her blouse. But at Melvin's door, she's embarrassed to discover that the wet blouse reveals a distinct lack of a brassiere.
Suggested correction: It shows no such thing. In fact Carol has been so thoroughly soaked that both her T-shirt and bra are wet and have become transparent as a result, and her boobs are showing through.
Not true. She has no bra straps showing when at the door talking, wet shirt. When she leaves and turns, the straps are present, wet shirt.