Can accidental death or injury occur on a large complex movie set?
With a cast of thousands (or millions) the simulacrum can easily produce real casualties.
In this clip from the 1975 Oscar winning film "The Day of the Locust", there are only a few "broken legs" and the insurance compensation payouts guarantee zero press coverage.
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As to the possible INDIVIDUAL ritual sacrifices, we can only speculate.
Film director Art Olivier, long employed around Hollywood and very familiar with the milieu, insists that individual ritual sacrifices of. a masonic (Satanic?) character do occur from time to time. But these are for INTERNAL discipline within the cult.
Gangsters do have to kill someone, from time to time, to reinforce discipline among the troops.
See the original meaning of the term "decimate”, from the Latin.