Cindy asked me who was my favorite mystery writer after I confessed to loving this genre.
P.D. James is who first comes to mind. I love that her mysteries are complex, wonderful stories with very well developed characters. Inspector Dagliesh which most of her novels are about is a policeman that writes poetry; reading each book is like reading about a friend you have known for years (and I have). I'm anxiously waiting for the next one, I worry because Ms James is now in her eighties. She also wrote two novels with female detective Cordelia Grey, but she never pursued this series, which received critical acclaim.
My next favorite is Elizabeth George who writes the series for Inspector Lynley. I love these books for the same reasons that I love P.D. James. Ms. George novels are grittier and more emotional with just as captivating stories and characters.
I have read many different authors that I enjoy, you can link to my GoodReads page on my sidebar if you are curious. You won't go wrong picking up a book by either one of these wonderful mystery writers!