Sinister Sudoku (Sudoku Mystery Series #3)

Liza Kelly, Sudoku Maven with the Oregon Daily, is conducting a sudoku class in the most unlikely of locales: the minimum security wing of the Oregon Coastal Penitentiary. The students are eager for the distraction—they have too much time on their hands. And some of them are surprisingly good at their lessons. Though she’s sad when her best student has to quit the class, Liza is thrilled because he’s about to be released from prison.

But he doesn’t enjoy his freedom for long. His dead body...