You’re sitting on the train, listening to the phone conversation of the girl next to you. (You’re not trying to listen, but it’s that level where you can’t tune it out, and you don’t have a pair of noise cancelling headphones with you. In fact, half the carriage is listening for that very same reason.)
She’s having boyfriend trouble.
“I think he wants to drop me. It’s our anniversary in three weeks. I found this lovely restaurant. But he says he can’t afford it. It’s an excuse. He doesn’t want to go out.”
Noises from the other end of the phone.
“No. He’s like that all the time. And it’s not as if he can’t afford it. We’re going to this expensive steakhouse tonight.”
More noises from the other end of the phone.
“He knows I’m vegetarian. He’s apologetic and all that, but it’s his father’s fiftieth birthday and his dad likes steak. So we’re going to this place tonight—fifty dollars a steak, where I can’t eat anything—and then he says he can’t afford to take us anywhere nice on our anniversary.”
A short reply from the other end of the phone.
“No. It’s just an excuse. He’s looking for an excuse to make me drop him. He’s too cowardly to do it himself.”
You want to lean over and say to her, “Maybe he really can’t afford it.” Half the train probably does too. But this girl wouldn’t believe you, because she’s convinced the boyfriend is looking for an excuse to drop her.
She’s an unreliable narrator, as far as her boyfriend is concerned, because she’s interpreting everything he says and does in a specific way, which is not necessarily how most people would see it. And because she’s interpreting it that way, you, the reader—or in this case the listener—get a very specific idea about this girl and her boyfriend.
What impression do you have of the boyfriend?
He gets on well with his family. He’s careful with his money, although he is prepared to overspend for an occasion. The occasion he’s prepared to overspend for is his father’s birthday, not his girlfriend. So, not sure yet about the relationship with the girlfriend. Maybe she is right that he wants out. Even so, he comes across as a nice, family-oriented guy.
She comes across as somewhat selfish, thinking more about herself than her guy. Thoughtless about finance. Unappreciative of a man who puts family first. Whether she’s correct or not about the boyfriend trying to get her to dump him? Don’t know. Don’t suspect so, but that is more a gut reaction to the character than a reasoned is he or isn’t he.
This is a great writing technique. Using a scene/conversation to convey something else entirely. It gives extra layers to your story, making it richer.
In another example, take the film-clip, above. Mr Bean and the two-way mirror. How you perceive this scene totally depends on whose point-of-view you are watching.
As they say in science, it’s all relative to your frame of reference.