A famous explorer was found poisoned in his tent in the middle of a hot desert. The cap of his water canteen was unscrewed and lying on the sand. Three companions brought him water at different times. Companion A brought water at noon, Companion B at 2:00 PM, and Companion C at 4:00 PM. The coroner stated the poison took effect instantly upon drinking. Detective Holt arrested Companion A. Why?
Companion A brought water at noon, but the explorer was found with the canteen cap unscrewed in the intense heat where water evaporates rapidly. Wait, if the poison took effect instantly, he couldn't have survived until 4:00 PM if A poisoned it at noon. He would have died at noon.
If the poison acted instantly, a victim given poisoned water at noon would die at noon, making later visits impossible.
About this riddle
Detective riddles are tiny mysteries. Look for the detail in the story that does not fit; it is usually the clue that solves the case.
Difficulty: Hard. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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