In a locked-room mystery, the victim was found with a frozen dagger made of tap water resting in their chest. The room had a roaring fireplace, and the heater was cranked to maximum. The detective smiled and said, 'The killer made one fatal thermodynamic error.' What was it?
The dagger would have melted before the police arrived
With a roaring fireplace and high heat in a sealed room, an ice dagger would have completely melted into a puddle long before anyone discovered the body.
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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