A locked-room mystery baffled the precinct: a man was found dead inside his study with the deadbolt thrown from the inside and the single key resting inside the room on a desk. The window was jammed shut from the inside with rusted iron nails. The coroner noted the time of death was noon. The detective looked at the ice block melting near the radiator and solved the case. How was it done?
The door was locked using a frozen water key
The killer used a key molded out of ice to lock the door from the outside, which then melted away completely by noon, leaving no key in the lock.
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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