An antique dealer was found dead in his locked vault. The heavy steel door could only be opened from the inside with a complex wheel mechanism, or from the outside with a mechanical digital keypad code. Detective Drake checked the security logs: no one had entered the code in five years. The door was locked when police arrived. How did the killer escape?
The vault was built with a hidden second exit or air vent large enough to crawl through.
If no one used the keypad and the door was locked from the outside, an alternate exit must have been used by the culprit to slip out unseen.
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.
More detective riddles
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