We can also use em dashes’ to signal that an interruption has taken place. It might be within the scene, or within a conversation, or even within a character’s own thoughts. Whatever the case, we can use an em dash to signal interruption. Here are some examples from within a scene, a conversation, and thoughts:

1) Ali had just walked into the palace. She was minding her own business when—CRASH—a vase dropped from the table where she was standing and smashed on the floor.

2) “I’m sorry,” Ali said to the King. “I didn’t mean to it was an acc—”

“—silence my child. I know it was not your fault,” the King said with a smile.

3) Ali couldn’t believe her luck. I thought he’d be furious. Everybody always said he was so cruel. Maybe he isn’t so bad after a—She shouldn’t have let her guard down so soon. The king’s smile had faded, and he had anger in his eyes.

As you can see from the examples above, we can use an em dash to show an interruption in a variety of different ways. Notice how when we use it in quotation marks for speech, we use it in the speech that is interrupted, and in the speech that is doing the interrupting and always within the quotation marks.