"The sound heard at the beginning and end of each act, when the scene goes to black and white is…"

“The sound heard at the beginning and end of each act, when the scene goes to black and white is Donald P. Bellisario making that noise into a microphone. He wanted a unique way of bookending each act and took a microphone and went into a studio and made that sound into the microphone. The use of the black and white stills or black and white clips are purposely intended to add a cinematic feel to the look of the show. It works.”

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It sounds like a pitched-down camera flash. I’ve already sampled it.