If you intend to read Fadeaway Girl, the latest in Martha Grimes' Emma Graham mystery series, you would probably do well to read the first three books in the series first. It is not that you can't understand what is going on without having read the others; it is simply that there are so many more or less cryptic references and connections to people and events in those earlier books that they inevitably get in the way of new story. Not having read the other books myself — until I went down to the local library and checked them out — I must say I often found myself confused.
Novelists writing a series are faced with the problem of giving new readers enough information to understand who everyone is and any background they need without boring their old readers by rehashing things they already know from the earlier books over and over again. The more recurring characters there are, the greater the problem. It is fairly easy to avoid the problem if your central character is a rootless loner who rarely stays in one place for any length of time, or if he or she is a professional of some sort always working on different cases with one or even a few allies. On the other hand, if your detective is a 12-year old girl tied to a small town at the very bottom of Maryland and its environs, where not only is she a waitress at her mother's hotel and a reporter for the local newspaper, but a super sleuth as well, it becomes a real issue.
It is not one or two or even five or 10 characters who move from one book to another, it is towns full of people: the waitress at the local diner and its grumpy owner, the sheriff and his demeaning deputy, the fellow who drives the taxi, the ancient great aunt who lives alone on the fourth floor of the hotel, and on and on. It is very easy to get lost in the crowds of people that Emma runs into in the course of her investigations.
Then there are the constant references to events that took place in other books, and which she can't seem to get out of her mind: how she was nearly killed, other murders — Mary-Evelyn Devereau, Rose Queen, Fern Queen, a kidnapped baby. Most of which, at least at first, seem to have very little relationship to what is going on in the present book. Indeed, at first one has to wonder what it is exactly that is going on in this book, outside of what may be growing out of a precocious 12-year old's active imagination. Her mind, as the sheriff says in the first novel, Hotel Paradise, may be "unlumbered by reality."