A security guard at a pharmaceutical lab reported that a vial of experimental serum was stolen during his night shift. He claimed a masked intruder threw a smoke grenade through the small, high ventilation grate, rendered him unconscious, and fled. Detective Cruz inspected the guard's uniform and immediately knew the story was fabricated. What did Cruz notice?
The guard's uniform was completely clean of soot and smoke residue.
If a smoke grenade went off near the guard in a confined space, his uniform would smell of smoke and bear soot stains. Since it was spotless, he was never near a smoke grenade.
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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