HR director Kat Voyzey has a talent for getting things done. Tamping down office drama? Soothing egotastic executives? Dodging calls from her bully of a boss? It's all in a day's work at the Holy Heart Medical Center. When a beloved coworker is shot dead on Halloween night, questions fly through the hospital like a hail of bullets. Is there a killer roaming the halls of the hospital? Will they strike again? And who would want to hurt sweet Anna Vasquez? Frustrated by a weak police response, Kat rolls up her sleeves and gets to work. She's accustomed to getting to the bottom of things, and she resolves to be super careful. How dangerous could a murder investigation be?