Inspector Vance found the victim slumped over a desk with a punctured tea cup, a fresh ink stain on his right index finger, and a sealed envelope stamped at midnight. The coroner noted the poison was inside the cup. Who poisoned the tea cup?
The victim
The ink stain on the right index finger and the punctured tea cup indicate the victim used the nib of a fountain pen to poke a hole in the cup, likely to drink hidden poison or testing it, though the text states the poison was inside the cup he handled.
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: Medium. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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