Arsenic and Old Books is the 6th installment in the A Cat in the Stacks Mystery series.  This is a really intriguing outing in the series, as Librarian Charlie Harris delves into the past through a set of documents donated to the library.  There are political shenanigans afoot though, and Charlie, with Diesel by his side,  and the documents find themselves in the middle of it all. Well done mystery plot, lots of intrigue, and clues to keep the readers guessing.  Highly recommended cozy mystery series.

I have to admit that I really enjoy all of the series that I have read from Miranda James/Dean James/Simon Kirby-Jones/Honor Hartman, but A Cat in the Stacks with sleuth Charlie Harris sticks out as my favorite of them all.