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Blues Brothers - always possible that Ray\'s store has a FOH sound board and desk feeding outside - or ambient mics...
Crumbs... I know I've seen a musical done in literature once. I'd love to add it if I could remember what it was. All I remember is that at one point the bad guy bursts into song and it's mentioned that he didn't feel like singing, but couldn't help himself (because that's how this world works).
In other languages and cultures, it's perfectly common that a song does not need a rhyming scheme. Therefore, musicals in many other languages tend to make more sense: putting a bunch of words to a melody is actually pretty easy when you've had some training and experience in the field and/or are naturally talented and/or already had words prepared (i.e. "If You Were Gay" from Avenue Q - it's quite possible that a bit of thought went into that before it was sung). So, aside from a ghost orchestra and hordes of trained dancers appearing, it makes more sense in other languages even without these hypotheses.
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