Frank's brain was...well, it was getting old. He couldn't feel it, but every time he had trouble remembering the name of an old buddy from the force, or something Marge had said to him, he knew.

So Frank started turning the daily paper to the crosswords and trying to work them out over breakfast. Then, one day, sitting at the diner over a plate of sausage and waffles, he found his eyes drawn to this Sudoku thing, a crossword with numbers. He did one. The next day he did another. The next, another. Then he bought a book of them and sat at the diner from breakfast 'til lunch, doing one after another. Then he started memorizing the puzzles, so he could do them without the book. The old detective's mind, normally agitated with memories of unsolved cases, was glad to latch onto the number puzzles as a distraction.

His memory grew stronger as he crunched away in his head, and the blank spots became less frequent, though he had picked up a tendency to yell out a number in his eureka moments, sometimes publicly. Women he encountered, in particular, tended to get very upset at the misunderstanding of his meaning, though a few men had also walked away confused, and quickly.