Double Indemnity (1944) 
A:     Walter Neff (Fred MacMurray)
B:     Barton Keyes (Edward G. Robinson)

A:      Know why you couldn’t figure this one, Keyes? I’ll tell ya. ‘Cause the guy you were looking for was too close. Right across the desk from ya.
B:      Closer than that, Walter.
A:      I love you, too.

Sunset Boulevard (1950)
A:      Norma Desmond (Gloria Swanson) 

A:      All right, Mr. DeMille, I'm ready for my close-up.

Ace in the Hole (1951)
A:      Charles Tatum (Kirk Douglas) 

A:      How'd you like to make yourself a thousand dollars a day, Mr. Boot?  I'm a thousand-dollar-a-day newspaperman.  You can have me for nothing.

Stalag 17 (1953) 
A:     Duke (Neville Brand)
B:     Harry Shapiro (Harvey Lembeck)
C:     Stanislas 'Animal' Kasava (Robert Strauss)

A:      What do you know?  The crud did it.
B:      I'd like to know what made him do it.
C:      Maybe he just wanted to steal our wire cutters.  You ever think of that?

Witness for the Prosecution (1957)
A:      Nurse Plimsoll (Elsa Lanchester) 

A:      Sir Wilfrid!  You've forgotten your brandy.

Some Like It Hot (1959)
A:     Osgood Fielding III (Joe E. Brown)
B:     Jerry/Daphne (Jack Lemmon)

B:      Well, you don't understand, Osgood.  Ohh! [removes wig] I'm a man!
A:      Well, nobody's perfect.

The Apartment (1960)
A:      C. C. Baxter (Jack Lemmon)
B:      Frank Kubelik (Shirley MacLaine)

A:       I love you, Miss Kubelik.
B:       Three.  Queen.
A:       Did you hear what I said, Miss Kubelik?  I absolutely adore you. 
B:       Shut up and deal.