A priceless sapphire was stolen from a locked vault. The suspect claimed he was trapped inside a soundproof panic room with no windows for the entire weekend. Investigators noticed a fine layer of white dust caked on the inside of his shoes, but nowhere else in the room. Why did his alibi collapse?
Drywall dust
The panic room's interior walls were made of solid steel, meaning there was no source of white drywall dust inside. The dust on his shoes proved he had recently kicked through a drywall partition elsewhere in the house.
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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