Darkfall by Dean Koontz

The excerpts follow a narrative structure, detailing a series of increasingly violent events related to a conflict involving black magic and a police investigation. Initially, the text presents supernatural occurrences experienced by a young girl named Penny, followed by the gruesome murder of a bodyguard, Ross Morrant, and the subsequent death of his employer, Vince Vastagliano, at the hands of demonic entities summoned by a powerful practitioner of voodoo named Lavelle. The primary plot centers on Detective Jack Dawson and his partner, Rebecca Chandler, as they investigate the unusual homicides while struggling to reconcile the horrific nature of the crimes with their professional skepticism.