Fault Lines (Fault Lines #2-3) by Tim Powers
 
Los Angeles is full of ghosts - real ghosts and solid ghosts, ghost hunters and ghost junkies - chasing and being chased in a mad quest for immortality. As a series of disasters strikes the city, the lives of three innocent people converge in a wild escapade through a landscape haunted by the dead, the mad and the just plain strange.
 
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