Guess Who's Coming to Dinner

Guess Who's Coming to Dinner is a 1967 film comedy, directed by Stanley Kramer and starring Spencer Tracy, Katharine Hepburn and Sidney Poitier. It's about the struggles of an outwardly-liberal couple coming to grips with the fact that their daughter is suddenly engaged to an African-American doctor.

The film was the most successful of Kramer's films, and Tracy's last film. It was so successful that it even killed the old bugaboo of fearing the loss of Southern state cinemas for any film starring an African-American. It was remade in 2005 as Guess Who, with Ashton Kutcher, Bernie Mac and Zoe Saldaña.

Guess Who's Coming to Dinner was added to the National Film Registry in 2017.

Tropes used in Guess Who's Coming to Dinner include:

Dating What Daddy Hates
Dramedy
Flat Character: A fairly common criticism of both John and Joanna, see below. Joanna originally had a passage of dialogue that could've potentially given the character a bit more depth, but it was ultimately cut.
Fourth Date Marriage
Happily Married: Matt and Christina Drayton. It's what gives Matt his eventual insight into why he shouldn't stand in the way of John and Joanna's marriage, and stands behind every line of his speech at movie's end.
Positive Discrimination: Poitier's character is so ridiculously perfect in every conceivable way that he hardly seems human. This was deliberate (if a bit Anvilicious) on the part of the filmmakers, so that the only possible objection to his marrying Joanna would be his race (and the fact she had only known him for ten days).
Title Drop: What Christina does when informing her husband that John's parents would be joining them for dinner.
Wide-Eyed Idealist: What Joanna comes off as. As John said, "It’s not just that our color difference doesn’t matter to her. It’s that she doesn’t seem to think there is any difference."