by Lilian Jackson Braun
The fourth book in Braun's The Cat Who . . . series, this book follows along with Jim "Qwill" Qwilleran and his two side-kicks, Siamese cats named Koko and Yum Yum. After the death of a family friend, Qwill realizes that something doesn't feel quite right about the death. When Koko begins pulling seemingly relevant works of Shakespeare off the shelf, Qwill must trust his instincts to solve a crime generations in the making.
This book was a fun, quick read. I don't think you'd need to read the other books in the series before dropping in with this one.