A museum curator was found locked inside a secure vault with no physical keyhole on the inside. The heavy steel door can only be unlocked by entering a rolling numerical code on an exterior keypad. The victim died of natural causes while inside. How did he manage to lock the heavy vault door behind himself from the inside?
He didn't. The vault door locks automatically when closed.
Most modern vault doors are designed to latch and lock automatically upon swinging shut, requiring a code only to open from the outside.
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: Easy. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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