Continuity mistake: In the intro, the protagonist is making his way through the crowd of autograph hunters. One of them asks him "Hey Rupert, who'd you get?" Rupert makes a dismissive gesture with his hand, at the cut he repeats it even when he had lowered his hand already. (00:02:05)
Continuity mistake: After Sandra Bernhard has been removed, watch Jerry dive back into his car. One of the people aggressively seeking him, behind De Niro, makes a frustrated gesture with an open right hand. In the next shot (when it's Rupert to sneak into the car), the same person is holding a yellow notepad. (00:06:20)
Continuity mistake: When De Niro's character gets in the limousine with Lewis' character he has a hurt hand. He wraps it with a handkerchief. As the scene progresses the handkerchief disappears and reappears depending on the camera angle. (00:07:15)
Continuity mistake: In a cringeworthy bit of prop comedy, Rupert hands Jerry the picture of his Pride and Joy; De Niro is holding the picture with the forefinger on top in the wider angle, but with the thumb on top in the close-up. (00:10:20)
Continuity mistake: In his third interruption to Jerry trying to get back to his apartment, Rupert does not have in either hand the wallet he pulled the Pride and Joy picture out of. When he is shown turning around saying "Okay OK okay", he is holding the wallet. (00:10:35)
Continuity mistake: In the first dream sequence, Jerry is taking one more sip of his drink when Rupert tells him "That's...the worst." His left hand is staying at the same level as before, but at the cut it suddenly dropped low enough to be out of frame. (00:11:35)
Continuity mistake: When Rupert in his dream is approached by a fan and asks her name (Dolores), Jerry Lewis has his left hand under his chin in the first shot, on the table in the next. (00:12:40)
Continuity mistake: Rupert reintroduces himself to the old schoolmate Rita. He gifts her with a rose; during this first part of the scene Rita's arm position and whether her palms face up or down changes between shots. (00:15:30)
Continuity mistake: During the conversation between Rita and Rupert at the counter of her bar (when she asks him what is he up to), the beer in his mug is slightly above/slightly below the handle as shot and countershot alternate. Likewise as the editing goes back and forth between those two angles De Niro is also touching the side of the glass with his finger or not. (00:15:50)
Continuity mistake: Dining at the Chinese restaurant, Rita asks a fresh refill of her drink. Throughout the scene, the glass appears in her hand seemingly at random between cuts. Not just that; the level of liquid changes as well. It is particularly obvious when she says that the mystery autograph looks like signed by "a retard." (00:17:00)
Continuity mistake: Putting away the autograph book, Rita says "Rupert, you have not changed." In this second part of the conversation, multiple times Rita's arms go from folded to uncrossed, and the glass like in the first part of the scene appears and disappears suddenly in and from her hand. (00:19:40)
Continuity mistake: On Rita's doorstep, Rupert says that he wouldn't want to impose. You can see Robert De Niro folding the jacket over his bag, but in the rest of the scene he holds the folded jacket between the bag and his body. (00:21:10)
Continuity mistake: Rupert is waiting by the public phone. A line of people are angrily trying to shoo him away since the nearby phones are not working. You can see the various phone receives hanging down. But the one to the left in the closer angles is correctly hanged up as if the phone worked. (00:25:20)
Continuity mistake: Margo Winkler's receptionist character phones to Jerry's assistant to ask about that Rupert Pupkin fella who just showed up. When she tells him that there's no record of his appointment, she is holding the telephone in two different ways in the two separate shots. (00:26:50)
Continuity mistake: Rupert is daydreaming about Jerry loving the demo tape and inviting him to his country house. Jerry sits down at the desk and puts the tape back into the envelope in one single shot, resolute. When Rupert asks him if he can bring someone, there's another shot of Jerry Lewis reaching for the envelope and putting the tape in it. (00:38:05)
Continuity mistake: A lady at a payphone stops Jerry Langford and asks him to sign her copy of a magazine for her. He is doing it, and before he finishes, a lady with a beige hat walks past him. In the next shot the lady is followed by a guy that appeared suddenly. Likewise, the guy with green pants that was visible in the first shot moved into the next street, by the corner. (00:39:05)
Continuity mistake: After the encounter with the cancer lady, Jerry is stalked by Sandra Bernhard. In his escape he traverse an intersection; people in the street and on the sidewalk change between shots. (00:39:55)
Continuity mistake: While he waits for the last word on his tape, Rupert has another dream sequence. He greets his old high school principal saying "Well how are ya?"; notice there's Robert De Niro's thumb popping in view in that close-up on George Kapp, but in the following wider shot, De Niro's hand is on the armrest. (00:41:55)
Continuity mistake: Rupert nonchalantly gets past the Asian butler Jonno and gives him his baggage and Rita's. He keeps to himself his 'work' briefcase, which is in his left hand as he says "No we'll just wait." There's a cut midsentence, and the object switched from left to right. (00:53:10)
Continuity mistake: When Jerry Langford tells Rupert "If I didn't tell you that, we'd still be standing on the steps at my apartment" he is leaning into the golf club held in his right hand. Cut, and you can see the club jumped to his left hand, and after the Hitler joke, the club is back in his right hand. (01:00:00)
