Nightworld by Patricio Valladares

4.38

When former LAPD officer Brett Anderson takes a job as head of security at an old apartment building in Sofia, Bulgaria, he soon begins to experience a series of bizarre and terrifying events. Soon after delving into the building's sinister history and investigate its shadowy owners and past employees, Brett uncovers a malevolent force nestled deep in the bowels of the building that will do anything to be set free into our world.