Inspector Vance found the victim slumped over a desk with a punctured tea cup, a fresh smudge of black ink on their right thumb, and an open book of poetry. The heating vent was blasting dry air. Vance immediately arrested the secretary for murder. How did Vance know?
The secretary
Black ink takes minutes to dry, but the victim was killed by a poison that acts in seconds. A victim poisoned instantly would not have a fresh smudge of ink on their thumb from writing just before dying; the secretary must have forged the final lines after the murder, accidentally smudging the wet ink.
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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