Bravo! Great episode Monk! I was watching some old Sherlock Holmes episodes over the weekend and noticed a very similar plot from a 1955 episode. I considered Monk's take an homage to this earlier work. And the 'chess-champion' twist is just what the doctor ordered. Loved it!
Mr. Monk and the Genius (2008)
Monk takes the case of a brilliant chess master's wife, who believes that her husband is about to kill her and wants him caught - posthumously.
The Case of the Perfect Husband (1955)
Russell Partridge announces to his wife Janet one day that he is in fact a killer who has murdered his six previous wives, and notifies her that she has one day to live and get her affairs in order before he murders her, too.