Inspector Drake inspected a counterfeiter's print shop. Thousands of fake hundred-dollar bills were stacked on tables. The suspect claimed he just started printing them that morning. Drake held up a bill, pointed at the serial number, and proved the suspect was lying. What was wrong with the bills?
The bills had identical serial numbers
Real currency has unique serial numbers for every single bill. Counterfeiters often make the mistake of using the exact same serial number across an entire batch of printed notes.
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.
More detective riddles
Detective Vance was investigating a forgery ring. He inspected three forged banknotes and noticed every single one of them had the exact same serial number. What did this tell him about the counterfeiters?
At the scene of the museum heist, the glass display case was shattered, but the alarm system was never tripped. The security guard swore he never turned it off. How did the thief bypass it?
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