Lord Blackwood was found slumped over his mahogany desk, a silver dagger in his back. The window was frozen shut from the inside, and the only door was bolted from within. A puddle of water sat on the rug beneath the open fireplace, but the logs were bone dry. The detective smiled and pointed to the melting icicles resting on the mantelpiece. How did the killer strike without entering?
An icicle dagger
The killer used a weapon made of ice (an icicle dagger) that melted completely into a puddle of water by the time the detective arrived, leaving no metal or wooden weapon behind.
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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