I have in my story a couple of scenes with verbal confrontations, where the protagonist accuses people who have been lying to her and they try to explain their side and reveal some shocking information.
I’m worried of making these scenes too static by concentrating only on the dialog. At the same time, I’m worried that including too many physical reactions risks making the scene melodramatic, especially since there are only so many gestures and facial expressions expressing anger or emotional turmoil. Do you have any advice for me?
When you are just starting the dialogue, try to give a sense of the physical space the characters are in. They can interact with things in the space such as leaning against walls, pulling out chairs, thunking down on the couch, clutching glasses, etc. The body language can also be as much about how they are interacting with the other person as simply showing anger. For instance, one person can start to storm off and the other person can chase them down. You won’t need movement or body language for every line of dialogue, but it can generally fit in pretty often without being too much.
That said, when dialogue gets intense, you’ll probably have a section where everything else drops away and it’s pretty much just the dialogue. That’s okay; when things are intense the pacing should be tighter, and the dialogue is what’s most important. If you’ve set the scene earlier, readers will remember the general environment you introduced for a bit. If you want, you can break intense moments up by looking for places to add dramatic pauses. Let a character stare and seethe for a moment, for instance.
There’s no quick answer; it’s just about balance. I have a post on pacing dialogue that might be a little helpful if you haven’t read it.