Suppose a sentence like this:
The same museum guard I foiled last month was stomping over. Evidently, something about my disguise didn't pass muster — maybe it was the wig — but I managed to cut a long gash in the painting before he tackled me to the floor.
So far, so good. But:
Evidently, something about my disguise didn't pass muster — was it the wig? The fake nose? — but I managed to cut a long gash in the painting before he tackled me to the floor.
First, is this an acceptable use of dashes? It wouldn't feel right to move the questions to the end of the sentence, because it has already moved on. But with two in there, it's a little busy, and the capitalization seems inconsistent. And how else might we do it?
Evidently, something about my disguise didn't pass muster — Was it the wig? The fake nose? — but I managed to cut a long gash in the painting before he tackled me to the floor.
Here the questions are treated as distinct sentences by capitalizing them, but I think it might make coming back to the original sentence more awkward.
Evidently, something about my disguise didn't pass muster — was it the wig? the fake nose? — but I managed to cut a long gash in the painting before he tackled me to the floor.
Here both questions remain uncapitalized, but it might feel a little sloppy or casual. Tell me what you think.
Edit: I wrote this sentence just for the question, actually hoping to avoid being bogged down by too much context, but since the first commenter felt it was lacking, I've adjusted the text a little bit. True, I could work around this sentence construction entirely, although it would impact the pacing. I also think it would shift the sense of the precise moment this character spends considering the flaws of their disguise.
As for the single em dash suggestion provided: "I didn't fool him — was it the wig? The fake nose? Either way, I managed." That can work, and I appreciate the answer. So would you say that I'm conclusively not allowed to do this with em dashes?