When Did Characters Become Meta?

When did characters in stories become self-aware of all the story tropes they are in and comment on those tropes during the story? In short, when did characters become meta?

I’m not quite sure how to pose this question so let me tell you how I got there.

In my SF book club this month, we discussed John Scalzi’s the Kaiju Preservation Society. It is a wonderful B-movie concept: there is an alternate earth where kaiju (i.e., giant creatures like Godzilla) developed and humans did not. The humans from our earth can travel between worlds and said humans study the kaiju and, well, preserve them.

The story takes place in early 2020 and is populated by a bunch of characters, most of whom are nerds. As such, they say and understand a ton of SF in-jokes, jokes that most of Scalzi’s readers will also get. Not a problem. It’s like writing for the choir.

But one of the book club guys made a point: at no time in the book did any of the characters have a Wow Moment, a sense of wonder moment reminiscent of that scene in Jurassic Park when the characters (and viewers) first see the dinosaurs. He went on to posit that basically up to the 1990s, many characters in movies (and books) seemed to exist outside of the present pop culture moment. That is, many characters didn’t have a handy shorthand list of references to speak about.

For example, in the Scalzi book, when something odd came up, all the characters in the book had to do was reference an existing movie moment and everyone (readers included) would know. (I did the same thing when I name dropped Godzilla a few paragraphs ago.) You could make the argument that Scalzi was not bothering to expound or explain something, but I actually don’t mind the shorthand at all.

We started commenting that many movies in at least the last decade+ are populated by characters like this and we tossed around the idea of when it started. Naturally, we arrived at the first Scream movie (1996) where all the characters knew all the tropes of horror movies and actually riffed on them and tried to overcome the killer by using those tropes. The movies of Kevin Smith are full of references like this, and some of the Marvel films reference Star Wars and other properties.

That got me to thinking about the mystery genre. Were there films, books, or TV shows that fit this type of story? The first thing that came to mind was the TV series “Only Murders in the Building.” I’ve not seen any of season 2, but season 1 had the characters basically do what Scream did for horror: narrate, in a meta way, the story they were in, commenting that in a normal true crime podcast cast, this is where a twist would occur…right before a twist in their own story happened. “Castle” had some of that mainly because the main character was a writer.

So, fellow mystery fans, I challenge y’all to help me out: what are some mystery stories of any medium where the characters basically comment on the story their in using tropes of the mystery genre?