On August 17, 1966, two Brazilian repairmen left Campos Dos Goytacazes under the guise of buying supplies and a car—which was meant to explain why they had a large amount of cash on their persons. They were spotted by a bartender as the men, Miguel Jose Viana and Manoel Pereira Da Cruz, stopped in his bar to get a drink of water. The bartender noted that Viana especially seemed to be in a hurry and kept checking his watch. It was the last time they were seen alive.

Their bodies were found three days later on Vintem Hill in Rio De Janeiro. They were dressed in suits, wearing waterproof coats. With them were lead masks (like you'd wear to protect from radiation), an empty water bottle, a notebook, and two towels. Inside the notebook was a confusing note in Portuguese which read:

16:30 be at agreed place, 18:30 swallow capsules, after effect protect metals wait for mask signal.

The money was gone.

Unfortunately, no autopsies could be performed, and there were no visible signs of death. All clues point to the chance they were duped out of their money, but the mystery still remains: What were they promised, and why the lead masks?