A jeweler was found locked inside his secure vault, unconscious. The vault door timer was set for two hours, and the heavy steel door could only be opened from the outside using a digital passcode known solely to the jeweler. When rescuers drilled through the hinges, they found the jeweler inside with a mild concussion and the safe empty. The jeweler insisted an armed robber ambushed him outside the vault, punched him, dragged him inside, and set the timer before fleeing. Detective Drake proved the jeweler was lying. How?
The digital passcode vault door cannot be set from the inside.
Since the vault door can only be locked and timed from the outside control panel, the jeweler had to have been outside to lock himself in, contradicting his story of being dragged 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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