A rare manuscript was stolen from a high-security vault. The thief left behind three identical photocopies of the first page, each signed with a different employee's name in blue ink. Detective Cross immediately knew which employee was innocent. Which one, and why?
The one who signed in blue ink
Actually, photocopies cannot capture original ink signatures; they print as black toner. If the signatures were in real blue ink, they were added after the copies were made, clearing the employee whose name was supposedly copied.
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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