A serial killer kidnapped five different people and sat them down each with two pills in their hand and a glass of water.
He told them each to take one pill but warned them that one was poisonous and the other was harmless. Whichever pill the victim didn’t take, the serial killer would take. Every victim somehow chose the poisonous pill and died.
How did the serial killer get them all to take the poisonous pill?
Neither of the pills was poisonous. The poison was in the water that all the victims used to swallow their pill.