A wealthy eccentric was found dead in his study, supposedly having locked himself inside to count his gold coins. The window was barred from the inside, and the heavy wooden door was bolted from the inside. Detective Vance noticed a small puddle of water underneath the door and a large gap at the bottom of the threshold. How did the killer escape?
An ice block mechanism
The killer used a frozen bolt or a block of ice as a temporary locking mechanism or door prop that melted away, leaving the bolt to fall into place from the inside.
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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