"Insight and appeal" - why, thank you, Library Journal! And yes, my Mr Grey - who is a cat, and was long before that other Mr Grey - does have both!
Dulcinea Schwartz's homeless friend Jeremy Mumbleleigh is accused of stealing a valuable book, but Dulcie knows the gentle Jeremy, who had a breakdown years ago, is innocent. It's spring break, and the library is in the throes of a renovation. As Dulcie investigates, more crimes come to light. This is the ninth entry (after Stages of Grey) in the series, and Mr. Grey, Dulcie's cat ghost, continues to provide insights and appeal along the way.