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"No one has escaped!" The guard pointed to a drawing on the wall of twelve detectives, waving. "The prisoners are right there!"

Well I don't know where the phrase "As smart as a guard" came from, but it wasn't coined to describe these particular guards. It took me twenty minutes to convince them that the real prisoners had escaped, which I finally did by erasing one of the detectives. You should have seen the guards' jaws drop when I did that. That's the first time I ever saw actual exclamation points and question marks appear above somebody's head. (In case you're interested, I felt one of the marks and they're made of hair.)