Sir Arthur was found poisoned in his locked study. There was no glass, cup, or bottle near him, and the medical examiner confirmed he ingested the poison orally. The window was bolted shut from the inside. How did the poison get into his system?
The postage stamp / Envelope glue
Sir Arthur was sealing a letter just before he died. He licked the envelope flap or a postage stamp that had been laced with a slow-acting contact poison.
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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