A renowned scientist was found poisoned in her sealed laboratory. The only way in was through a biometric retinal scanner lock that required her own eye to open. The log showed her eye opened the door at 9:00 PM, after her estimated time of death at 8:00 PM. Detective Sterling smiled and solved the mystery. How did the killer bypass the door?
The killer
A retinal scanner checks for blood flow and living eye pressure, but some older systems or forced overrides can be triggered using a severed retina or mechanical bypass. Wait, a simpler physical trick: the body was propped up or the scanner was tricked using a contact lens, or the time of death estimate was wrong. Let's use a simpler clue: the log recorded an entry, but the body was already inside. A retinal scanner doesn't require the person to walk in; the killer used the victim's living eye before she died, or propped her body up. Let's refine: The log showed her entry *after* death because the killer manipulated the digital system clock, or used her contact lens.
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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