There have been instances of performers falling into the orchestra pit. It can be very dangerous to the musicians…

Sometimes, singers get off or skip a bar. What ensues is kind of cacophonous and pretty scary if you’re the conductor. Many people will notice though it usually doesn’t last long! I already told my story at the Paris opera of the electricians going on strike in the big ending of my overture to Faust. In the darkness, the orchestra just played on by memory. It was quite amazing!