The Odd Couple (1968)

Other mistake: In the opening credits, the copyright year is shown as MCMXLVII (Roman numerals for 1947), when it should be MCMLXVII (1967).

Revealing mistake: When Walther Matthau is making sandwiches for his poker pals (during the movie's first poker game), Matthau drops a slice of bread on the kitchen floor. If you look at his hand, you'll see that he flicks his thumb to make the slice of bread fall.

Continuity mistake: In the opening sequence, Felix (Jack Lemmon) goes into the Metropole Cafe. One of the people he passes as he enters is a young woman with a thin face and very distinctive nose and eyes. He goes in, has a drink, hurts his neck, and leaves. As he is leaving, the camera pans the band and go-go dancers. One of the dancers is the young woman who had just left as he was entering.

Oscar Madison: I can't take it anymore, Felix, I'm cracking up. Everything you do irritates me. And when you're not here, the things I know you're gonna do when you come in irritate me. You leave me little notes on my pillow. Told you 158 times I can't stand little notes on my pillow. "We're all out of cornflakes. F.U." Took me three hours to figure out F.U. was Felix Ungar.

Felix Ungar: I'll be in the way.
Gwendolyn Pigeon: How could you possibly be in anyone's way?
Oscar Madison: You want to see a typewritten list?
Gwendolyn Pigeon: Oh, haven't you said enough already?

Vinnie: I thought he looked edgy the last couple of weeks. Don't you think he looked edgy?
Speed: No, as a matter of fact, I thought you looked edgy.