Detective Lane walked into the study where the safe was blown open. The victim sat at the desk with a pen in hand, having written a final note: 'My killer is my loyal nephew, who brought me my morning coffee in a red mug.' Lane immediately arrested the nephew, not for the note, but because of a glaring physical contradiction in the room. What was it?
The victim was colorblind or the room was lit by monochromatic light
In a classic trick, the room had no lights on and the blinds were drawn tightly shut, making it pitch black; the victim could not have seen or written that the mug was red.
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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