A valuable manuscript was stolen from a university library. The thief left behind a muddy footprint near the window. Detective Gray gathered boots from the four student suspects: Al, Bob, Cal, and Dan. Al's boot had a deep zigzag tread. Bob's boot had a circular waffle tread. Cal wore loafers with zero tread. Dan wore smooth dress shoes. Gray shook his head. 'None of your boots match the footprint,' he said, and arrested the librarian instead. Why?
The librarian did not wear boots or went barefoot, or the footprints belonged to the librarian who tried to frame the students.
Wait, if none of the boots matched, why arrest the librarian? Let's make it simpler: The muddy footprint was a left boot size 10, but the librarian had only one leg and used crutches. Let's do a cleaner logic riddle.
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: Medium. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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