I'm writing a scene where someone is having a telephone conversation, and my MC is listening from across the room. Not very polite, I agree, but we all do it. What is in this conversation is important, though, but he can only hear half of it. What would be a good way to write this one-sided dialogue?
Oh just write the dialogue he can hear and with his reactions splitting up the lines of it. "...He got it stuck where?" Keith's eyebrow raised. "What was he even doing with a gallon of amyl nitrate?" Keith's head spun, straining to hear the other voice. "Ok, ok... Just pay them off and tell them he won't ever get their monkey high again." Keith shook his head and did his best to pretend he wasn't listening.
Is your main character also your point of view character? In other words, are we getting the story from her perspective? If so, try to give us her response to what she's hearing, as she's hearing it. And be wary of giving us the entire one-sided conversation, if it's full of filler remarks. Try to give us the important bits of the conversation/tone or whatever is important to your main character. All the uh-huhs and 'fine-how-are-yous' can probably be left out. The key here is to give us the main character's reaction to what she's hearing. When the speaker says something, how does it hit the eavesdropper?
That's a fair point. Run us into the dialogue first and tell us the guy is listening in but only have us read the dialogue that is actually important/interesting/taken the wrong way.
I apologize for not giving much information. The story is 1st person, so it's all from his perspective. The scene I am trying to write has him listening to his girlfriend talking to his estranged father in an attempt to help rectify their broken relationship. It's important for me to get this right because the MC also learns a lot about how she feels about family, and more importantly, how she feels about him.
Oh in that case then it's no problem at all. You have the dialogue the guy is hearing and you can have his internal monologue reacting to it to split the lines up, you don't even need to show him physically reacting.