What started me thinking about this was They call me MISTER Tibbs! It’s a famous line delivered by Sidney Poitier in In the Heat of the Night, but they used it as the title for the sequel starring Poitier (I assume it did midlin’ well at least, because there was a second sequel, The Organization)
That got me thinking about other such films
"Play it Again Sam" – not the real quote from Casablanca, but the famous misquoted version, and the perfect title for the Woody Allen film, based on his play, and starring him (although, mercifully, directed by Herbert Ross – Allen’s directorial style back then wouldn’t have worked for this one)
What’s Up, Doc – Peter Bogdanovich’s hllarious screwball comedy starring Barbra Streisand and Ryan O’Neal. I guess the title conveys the mood, but it doesn’t have much to do with the plot, even though Streisand actually says it, and they end the film with a clip of Bugs Bunny and Elmer Fudd singing the line.
If you broaden it to include plays, you could do an entire class of Shakespeare-inspired titles:
What Dreams May Come
Brave New World
The Fault in Our Stars
The Dark Tower
Something Wicked This Way Comes
North by Northwest (sorta)
To Be or Not To Be
Outrageous Fortune
The Undiscovered Country
And many others
What else you got?
(I don’t think the George Segal comedy The Black Bird counts – it’s not really a quote)