An art collector was found shot in his locked gallery. The room had no windows, and the heavy oak door was bolted from the inside. A small puddle of fresh, unfrozen water sat directly beneath the air conditioning vent, even though the AC unit had been unplugged for three weeks. Detective Vance looked at the puddle and solved the murder. What was the weapon?
An icicle
The killer used an icicle as a murder weapon (or a frozen bullet). As the ice melted in the warm room, it left a puddle of water and vanished without a trace, explaining how a locked room mystery was accomplished.
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: Easy. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
More detective riddles
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