Black Magick #1 by Greg Rucka

A veteran detective who secretly practices witchcraft is called to a tense diner hostage crisis where the gunman inexplicably demands her by name and reveals he knows her hidden life. Straddling duty and the occult, she works a subtle spell to gain advantage, but the standoff ends in a sudden, uncanny blaze that suggests darker forces are in play. The case sets a moody tone of crime and sorcery, hinting at a larger conspiracy watching her every move.

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