Micheline is the youngest of the Helsing family, founder of Helsing Corps, the premiere agency for battling ghosts, zombies, reanimates, spirits, and other things that go bump (and rip and tear) in the night. As a tetrachromat, Micheline can actually see ghosts, and along with her squad of fellow Helsing students, she goes out nightly to help protect the San Francisco area. Set in an alternate reality where the Helsing, Harker, and Stoker families formed an anti-spook organization after vanquishing Dracula, Micheline and her cohort use a combination of weaponry, photography (something about capturing ghosts images on film), and technology to eliminate corporeal and noncorporeal supernatural beings.

Very ambitious in spots, with attempts at explaining how mirrors can be used to trap ghosts and visit the Obscura, the other side of the mirrors where ghosts apparently dwell if they can't/won't go wherever people are supposed to go when they die. This book is a lot darker and more grim than others of the YA horror genre (not Marbury Lens horror, but definitely nasty in spots - some gore is described, some mentioned in passing, as eyeballs roll across the floor. Creepy, effective, requiring more though than I was willing to put into it to follow the logic of the mirrors.