Olivia Waite is a romance author, practicing feminist, and wide-ranging dilettante.
Combining fantasy with mystery is always a gamble: mysteries rely on an reader's ability to play along with the detective and decode the clues, while fantasy thrives on the creation of strange new worlds and expansive magics that don't necessarily follow conventional physical rules. An author has to set up a system complex enough to sustain a puzzling mystery, but plausible and interesting enough so the reader plays along with the rules she knows are invented.
Max Gladstone's solution here is ingenious: he makes magic out of contracts and bureaucracy, turning souls into currency and building a financial-legal puzzle around the murder of a god. I loved magician-hero Tara Abernathy's wariness and those moments when she took real and slightly scary delight in the sheer power of her Craft -- and I loved chain-smoking priest Abelard, who's out of his depth and lost without his god's guiding light but does his best to find his way in the darkness. Very nearly a perfect book, and well worth the time.