Inspector Vance found the victim slumped over a desk with a punctured tea cup, a fresh smudge of graphite near the rim, and a handwritten note that read: 'The bitter herb brings final rest.' Vance immediately arrested the secretary. How did he know it wasn't suicide?
The graphite smudge
Graphite is lead from a pencil, not a natural part of tea. The secretary must have poisoned the cup with crushed pencil lead, leaving a physical trace that ruled out a natural or self-inflicted death.
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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