I'm not sure how this could be potentially dangerous short of someone having a heart condition but I have to give the Brazilians credit as this sure would scare the crap out of people.

As would this one

Scary Elevator Prank - YouTube

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1982 300GD Carmine Red (DB3535) Cabriolet Parting Out
1990 300SEL Smoke Silver (Parting out)
1991 350SDL Blackberry Metallic (481)

"The thing is Bob, its not that I'm lazy...its that I just don't care."