I just read Healey's second, The Shattering, and it's quite good, too. It's much tighter than Guardian of the Dead-- the plot and the theme are better integrated, and the pacing of revelation is much better controlled-- though it is also pretty predictable if you've read American Gods. Or The Golden Bough. Or a lot of things. But she managed to make that not a problem-- her characters haven't read those, and my having a level of knowledge that they didn't turned the plot from a whodunnit into a thriller. I was deeply invested, despite seeing most of the plot twists coming a mile off.